My take on that requirement is that the spell can be designed for multiple targets, provided they are all known at the time of the design. I suspect that the authors probably just wanted to avoid the awkward phrasing of "target and/or targets" and instead just said "for a particular target." By English syntax I don't think your cited statement precludes that interpretation.
What does the rest of the troupe think?
I would think that a spell with a target group could be made for a specific group...
I concur. If the target is "Room" a specific Room can be defined. But for an target Individual, only a single person could be so defined.
I still disagree, and I'll explain why. My understanding was that the important thing was getting the particulars of the target (e.g., horoscopes, etc.) before the spell was designed, so it could be catered to the intended target(s). P. 168 of the ArM core rules talks about a powerful spell not causing warping if "it was specifically and carefully designed to work on them." It then goes on to talk about "the target," but I think that's just by way of example. I don't think it precludes having two or more people designed for a given powerful spell.
Consider Group target spells, as silveroak mentioned. Presumably you can cater the spell to a particular group of people if it's target is Group. And if you can cater a spell to an entire group of people when it's cast collectively, why can't you cater it to a group of people when it's cast sequentially? That would make no sense.
Then there's the question of Room or Building or Circle or Ring spells. Does a Room spell not warp anyone targeted in the specific room it was designed for?
I think potentially if you have some sort of principle of thaumaturgical geometry where the spell could resonate with a particular room so it would not warp those within... that might require a related virtue however...
of course the question is if you design a spell for a particular group what happens when you change the group by one person- does it then inflict warping? If we allow more than one person to be designated as the target then we need to have some limitations- based on magic theory perhaps, with other virtues perhaps influencing the outcome? (I can also envision a MuVi spell that adapts another spell to not warp a different person...)
I think adjusting spells to more then 1 person need something the size of a minor breakthrough or minor (Mystery/Hermetic) virtue as it reduce the people affected by warping a lot and can be the path toward longevity get full integrated into hermetic theory as a spell/enchantment guideline instead of a function that have special rules.
Edit Although I would see such a breakthrough/virtue more toward a bloodline then a free to chose group
So, you're saying that you don't believe that you can cater a spell with a target of Group, I assume?
If we allow group then the only way I see it can work is that its only one specific group of people and only if all of this people are present and affected by the spell /ritual the no warping count (in case of attribute improvement the 1-3 casting). But then also the next one will ask why circle target should not be able profit from this aka circle - moment ritual and why longevity ritual can't be done for groups.
Edit: Also we have the target Fait and Dominion and they can extend the possible targets affected in one casting by a lot (especial in combination with the communion range although the spell level would go beyond good end evil)
When I read the words "specifically and carefully," I interpret that a single target can be defined at the time of spell creation. having two Individuals for an Individual-targeted spell isn't "specific"
I guess the answer is Circle - we make a ritual room in our main building, with an inscribed circle, and anyone inside the circle can receive the effects of powerful spells without warping. If the circle is ever damaged, repairing it won't make it the same, and so we'd lose that benefit. I'm not sure I like it, because it allows us to affect many people inside a circle. We'd have to redevelop our spells to use that circle. But if Poenitens redevelops his Stamina-enhancer spell, we could have a bunch of covenfolk and others get a boost to Stamina, in addition to a magus who needs it.
If the ring is broken, it's an automatic botch.
What do others think?
Circle means that the area is prevent from the warping and not the person in it. Because a rooms and areas can also gain warping it will even make sense to design a powerful circle spell for i.e. your summon circle.
That is why we are talking about group or simmiliar targets that increase the number of targets instead of effects that go for a area.
Well, I think that spells ought to be designed for more than one person, but I can see I'm not winning that argument. 
I would agree with ring spells being designable for a specific ring and not warping anyone who is subject to the spell in that particular ring, as you suggest.
A circle Target "affects everything within a ring..." p. 112 ArM5. For non-Warping powerful spells. "...only the designated target, and the caster do not suffer Warping unless the effect is also continuous." p. 168 ArM5. So I say that we can make a specific circle the target of Gift of Reason, and anyone inside will advance without warping. The spell doesn't affect the floor, and I see this as a target for a number of CrCo rituals.
I agree. A teleportation circle (e.g., using Leap of Homecoming with Circle target) operates to teleport what's in the circle to a new location. It doesn't teleport the actual circle.
I agree with you.
Ok as I'm not strict opposite to this way of interpretation how about the idea that a circle and group spells can be specifically be created to not warp the people affected in the first second after the very first casting took place.
For circle this means its nearly impossible to replicate it as it would have to be the full area and all that was within it at the first casting must be present in the next circle (just a insect no longer there would prevent it)
... sorry circle target, touch range with moment duration is +1 so there have to be limitations compared to group + voice range+ moment duration (+4).
While for group it just have the same people of the first casting affected, if there now more affected its no problem as just the more people get normal warped but if someone is missing then all get the normal warping.
I think this rule for group also can easy applied to target like Faith or Bloodline.
Edit: after reading trough my idea again it sound like a astrological attunement toward the circumstances of the first casting instead of a specific target but that should be fine.
jeason72 brought up a really great idea: a No Warping Spell Mastery that give a additional target that isn't warped from the power of the spell per level of the Spell Mastery.
I think this is superior to all the other ideas we came up so far and also allow to later add new targets as well. It also give reason to master some spells we wouldn't even think about to master with the options we have so far.
But most important it prevent that we invent touch + circle + moment rituals en mass when this rituals are actual just supposed to be touch + ind. + moment.
(There already way to many reasons to go for circle target instead or individual so we don't need to add a extra one)
I was giving my companion some thought, and I must say I'm intrigued by the rules in C&G. But silveroak is doing a craftsman and I don't want to be a copycat doing the same thing as him.
One alternative I thought was to make up a companion who's a trader rather than a crafter. That would let me come at things from a different angle. In fact, given that we are likely to be playing a high-level game with politics playing an important role, I was looking at the possibility of making him a capo/partner for a trading house. The only problem with that is that the starting wealth for a capo is pretty high. They have access to a Greater income source (250 MP/year), which may well be too high.
My thoughts are that two things may mitigate matters. First, money does not seem to be a real concern with this covenant. We have a Legendary income source, which provides us with more money than we could ever spend. So having someone else who was wealthy might not be as unbalancing as it might be if we were a starting covenant just scraping by. Second, the stories we seem to want to tell in this saga are bigger than in some others. We're looking to see how magi can integrate with the mundane world, and that means we're likely to be dealing with some of the movers and shakers in the Greek world. With that background, I don't think a capo would be too out of place. In many ways it's less about the money than the stories you can be in when you're a capo.
Nevertheless, I'm putting this before the troupe to see what you all think. Would a capo be too much for this saga? I'd prefer to have my companion be a capo, but if people think that's a problem I could downgrade to just a factor.
So, let me know what you think.
Because Capo is a Major Social Status I suppose that means he don't work for the covenant.
So the first question is how is he linked to the covenant and the second is why is the capo joining stories around the covenant.
Yes I also have the problem that I always have come up with some idea why my companion would join a story because he isn't direct part of the covenant.
(That why I'm thinking about to drop the wealthy and take the Redcap social status instead)
I thought one of the points of companions was to have more complex characters. Grogs are the people who work directly for the the covenant. Companions are people associated (for whatever reason) with the magi. I’ve been in other sagas where companions weren’t working directly for the covenant and that’s worked out just fine. And I can think of plenty of examples of “independent” companions who would have more than adequate reason to associate with the covenant and take their part in stories.
Major social virtues are there for companions. Grogs can’t take them; and magi already have the social status of magi. Why have major social status virtues if not for companions? Companions are there to explore those major roles.
That’s an easy question. First, I’ve figured my companion will take the Magic Fascination flaw. In his back story he discovered the covenant and was fascinated by the magic they do. He sticks around, helps out, and otherwise gets involved because he loves being part of a magic world. Really, a companion just has to be willing to help the covenant. He doesn’t have to be working for the magi. Working with the magi is enough. A companion who’s a friend of the covenant is just as likely to want to be involved in stories as anyone.
As I said, the companion just needs a reason to want to help the covenant. He doesn’t need to be an employee of the covenant. Plenty of non-employee companions fit that bill. Consider the concept of a noble who’s a brother to one of the magi. That’s a perfectly reasonable concept with a major social virtue that doesn’t work for the covenant. The noble has plenty of reasons to stick his nose in covenant business and get involved in stories, despite not working for the covenant. A magister in artibus might technically work for a university, but in reality spend much of his time working with the magi. As you note, any companion with the virtue Wealthy technically doesn’t “work” for the covenant. But that’s a perfectly valid virtue to take.
You’re looking at having a nephilim redcap? Isn’t that hitting a lot of marks?
Frankly, if people nix my idea of a capo, I’m thinking of pitching a redcap.
Its fine, I only had game so far where the Companion also where direct part of the covenant so I wasn't that sure if external Companion work out that great and only because of this I was thinking about the Redcap idea.
A Capo Companion seems like an excellent idea to me. He provides a way to get news and draw people into stories.
Antagonists may want to horn in on his scheme, as the tales of our wealth spread, and we're known everywhere.