I can certainly see the use for this spell. In terms of the spell as suggested I am in line with Fruny's feedback on it. And having an Arcane Connection it should also be possible to use other factors in the penetration like horoscope, name etc from the penetration table.
Having given it a little thought I think there are other and perhaps preferable ways to reach the same goal. In fact I think that using a Watching Ward is only neccesary if you have to be gone for a long time and/or have little time to prepare your departure. If that was the case, and if you knew the Watching Ward spell you could spontaneous cast the Alarm spell - this would require little time but your Casting Total would probably not leave much for penetrating your own parma. Also, the Watching Ward would only work once - and it would cost you vis to make the ritual in the first place. Vis cost, one use only and an effect that might not get through your parma doesnt seem an attractive solution.
What would the alternatives then be? As you would have to use vis on the WW in any case you might aswell go further and make an enchanted item, which would also cost you vis but would be made to have a continuos effect - so that you'd never have to once more use the WW and more vis. Another solution would be to develop a spell in the lab that you cast your self, and not on yourself but on the door as the target, so that you dont have to beat your own parma. The dilemma then would be the duration - with a regular spell you wouldnt be able to make it last more than a month - unless you make it into a ritual and then a year at most (which again would cast your vis, but at least wouldnt have to penetrate your parma). So the question is for how long you'll be away?
I have tried to make some suggestion on how such a spell might look. I am uncertain about some of the calculations - I will explain below.
Undisturbed It Shall Rest
InHe 30
Range Arc
Duration: Moon
Target: Ind
(Base 2, Arc +4, Moon +3)
Since you cast this spell on the door before setting out, you do not need to penetrate your parma and thus you do not need to factor in penetration. A Casting Total in the 20 would be sufficient. This is the most straightforward way to make this. I was in doubt whether the base should be 2 or 3, but I do think it is reasonable to set it at 2. The guidelines divides the two by "locate" with "generel information". Any comments?
Undisturbed It Shall Rest
InHe 35
Ritual
Range Arc
Duration: Year
Target: Ind
(Base 2, Arc +4, Year +4)
This is the longer duration spell - as a ritual it would cost you vis, but on the other hand you would be sure of its success - there is no parma to penetrate.
Undisturbed It Shall Rest
InHe 10
Range Touch
Duration: Moon
Target: Ind
(Base 2, Touch +1, Moon +3)
This spell is a long strech and it made me start a new thread bc of the questions it made me ask of myself. The RAW says under Range (p. 111) that "A spell that has a continuing effect remains in effect even if the caster moves out of range." This is pretty straightforward concerning most spell bc they often have an effect here and now and what the spell then does is to keep up the effect (the muto'ed soldier stays a pig untill the end of the duration whether the magus keep looking at him - Sight), but what if the effect is to give the magus information and nothing more? In this instance to know whether a door stays closed. If this is possible then the magus could cast the spell on the door at Touch range and travel away and still know whether the door stays closed. On the other hand, spells that involve an ongoing control require you to be within range to control, though the spell will continue to work even if he moves out of range, but.... is the information gained by a intellego spell equivalant to control? How does range affect ongoing intellego spells?