FPP is indeed a prop protect mod.
But it may not be breaking ULX so much as you (likely?) have it misconfigured, or it added itself to a group it maybe shouldn't have.
Problem 1) Your trial mod is set to not target itself instead of the group "above" it.
Answer 1) Set can target on trial mod to !%admin (instead of !%trialmod)
Problem 2) Your trial mod also has ULX physgunplayer access (meaning it can pick up anyone not target allowed)
Answer 2) See answer #1
Problem 3) Your trial mod inherits user. You now have a "split" in the group line. Two groups, operator, and trial mod, both inherits user. Though, technically, group lines can have splits, until you master inheritance and can_target, we don't recommend it for those who aren't experienced with the power yet.
Answer 3) Operator is just a 'default example' group we created for ULX inheritance. If you aren't going to use operator, set admin to inherit trial mod, then delete operator group. If you are going to use operator, set admin inherit trial mod, set trial mod inherit operator, operator can target !%trialmod, user can target !%trialmod
(! = not, %=group including inheritance)
Problem 4) Your Trial mod group has a FPP access I know nothing about, but from the title "fpp_touchotherplayersprops", would seem to indicate they have access to touch others props. (Seems obvious title)
Answer 4) You need to figure out from wherever FPP is supported how to correct that access, or limit that access to same group and below. FPP MIGHT follow ULX group inheritance and targeting using an API called CAMI, but I don't remember
Fixing 1,2,3 may fix 4.
