Conflicting spells and stange situations Options

[Joker9125]

In a run i did i had the team break into an apartment and "convince" a guy not to testify against a mob bosses grandson. Knowing the team and figuring on everyone having improved invisiblity i had a thought. If i give the swat team mage that is helping to guard the guy trid phantasim i can make the player characters visible!!! Trid phantasim is awsome i simply had the mage cast it and make an illusion of those characters standing, walking, or running where they were, now this brings me to my first question. Since both spells affect the same part of the brain and would contradict each other in that situation how do you determine wich one wins? When I did the trid thing the character ducked behind a door to get full cover modifiers. Now herein lies the problem with this. This was an average sized door and even though this guy was a dwarf he would still take up a good bit of the width of the door. Think about it, if you were standing in front of a door while someone in shotting at it you would have a pretty damn high probability of getting hit espically if the attacker was using an assault rifle like these swat guys were.

My personal thoughts on these situations is as follows

For conflicting spells use a force test
For the door thing or similar situations use supressing fire rules but allow for some damage stageup.

Any suggestions? or better ideas?