Isn't it strange that it's easier to create something permanently (Momentary Duration) than just for a certain amount of time? I thought I read somewhere that you need Vis to create something permanently, but so far I haven't anything that cements that belief. Actually the Touch of Midas goes to show that you probably don't need it...
Well, it is a ritual. Therefore it needs vis.
If you made a non-ritual version of it, that gold would vanish in an instant.
Yes, I honestly think that it is.
In prior editions, there was the Permanent duration above Year. However, it was rarely used in practice and many spells had "split durations" where if cast normally the spell might have a Sun duration but if cast with vis the spell became Permanent. This edition clarified and rationalized the spell guidelines, doing away with split durations (which is good, IMO, because they were honestly a more than a little confusing) but (IMO) unfortunately also doing away with the Permanent duration in favor of Momentary Creo Rituals.
ArM05 , page 112.
As was pointed out , all Rituals require vis. (page 81 , ArM05)
I run with permanent creo rituals requiring triple amount of Vis. It never made sense to me that lasting creation should require nothing above normal rituals.
I use +2 magnitudes for ritual permanence, and +20 magnitudes for nonritual(but still use up as much Vis as ritual).
Also allowing permanent Muto and also requiring using the permanence duration for any Perdo that creates a nonnatural state.
+20 magnitudes??? 100 levels?
Ah, I see it, you allow non-ritual spells to be permanent at the cost of +20 magnitudes.
shudder
Clearly, we're not playing in the same leagues Has this even been cast?
Most of the ritual creation spells are rituals only because they create a permenant effect and so cost Vis for the ritual only becasue of the creation effect. Charging extra vis seems harsh, unless you are runnign a very Vis rich saga and need to soak it up from circulation in which case a better solution would be to give out less vis (Of couse my saga's tend to be vis rich even when i don't mean them to be)
That sounds like a joke - since that would make the spells at least lvl 85 (if the base was lvl 1) - and any spell of lvl 50 or more is ritual in any event...
Ah, I seem to have missed that it actually is marked as a ritual. Strange, I thought I had checked for that. ponders
Well, thanks anyway for clearing that up. 
Actually i have considered raising it further. Because yes it most certainly has been cast, and with some very low level base guidelines there´s room for abuse.
+100 levels isnt actually so horribly high or unattainable once a character has been around several decades.
Its not quite so hard as it sounds really. Even if normally only specialists can do it within their speciality(and Focus and/or using Life Boost or other similar things)...
Stamina +3, Aura +5, Art1 +25, Art2 +25, Focus+25, Life Boost+20, Dieroll +5, Loud+Exaggerated +2...
That allows you to cast a level 120 spell.
And using Affinity and Puissant in both, 2 Art Scores of 25 doesnt even need 400 XP. With around 750 XP you can get 2 Art Scores of 35. With a Focus, that alone gets you level 115 spells. With the other basic additions you´re quickly up at level 130 spells(level 150 with Life Boost). And if you started with a Base Guideline of 1 or 2, thats enough to start creating lots of stuff permanently.
So actually, you´re quite wrong about "not playing in the same leagues" if just looking at that.
If then adding houserules, the average Art scores goes up slightly overall and TeFo totals for specialists goes up maybe 5-20 depending on how extreme... And that means the ability to add LOTS of +Size modifiers to the spell, and OUCH... That has gotten slightly out of hand a couple of times. Still, the popular vote on it was overwhelmingly and almost completely in favour of the possibility existing, even if extremely high.
If we ever get around to another serious game of AM, i may raise it to +30 Magnitudes instead.
And many are the times looking at making the Ritual modifier higher as well, maybe +5 or something.
Based on comparison in an earlier thread here, we have tended to run low to middlish on easy Vis access.
Certainly below average at least. The basic idea has always been that if characters wants more Vis, they have to go out and get it, trade for it, hunt down creatures with it or locate new easy sources. Or simply extract Vim Vis for direct use or trade.
I was rather astounded how Vis rich some people run their games. And its not like we ran out of Vis often either.
Not here it isnt. The joke is the RAW rule that anything ABOVE level 50 must be a ritual, because there´s no good reason for such a cutoff point. Instead we made it a little easier to raise the casting total by using Rituals.
So a character who is uncertain or unable to cast a spell nonritually will often be able to do it by making it a Ritual spell.
And a level 50 spell does NOT have to be ritual even by RAW.
"may not have a level greater than 50" is the exact RAW wording.
You really should post your house rules along with your solutions to problems because the rest of us CANNOT cast a nonritual spell with +20 magnitudes.
And the 50 limit may have been included because the human will can only bend reality so far on it's own or somthing like that, just saying
I´ve been meaning to for a looooong time now, but i never seem to get it done. 
As outlined in the previous post, its really just a matter of actively trying to become able to cast highlevel spells.
Of course, if you dont play very long in ingame-years(or start out with older characters) you wont ever get to that point with any characters.
But hard or impossible its certainly not.
Still far too arbitrary for me.
The point i was trying to make was that we can only possibly assume that you are useing the rules in the book other than house rules that you specifically mention. Making it rather hard to understand how your fixes work.
It's not that our characters cannot achieve a casting total over 120 or what ever, it's that without the inclusion of your house rule we just cannot even try to cast a spell that level without it being a ritual and requiring vis.
Are we forgeting that a Ritula Spell requires ever a stress roll, Fatigue and 15 minutes by magnitud that are ever more that four?
In a ritual there are many things that can be wrong: saboutage, botches, etc... They make major effects because the risk.