I assumed "For some reason, when a Mouse gets killed, it respawns in the middle" meant that it shouldn't be respawning, and especially shouldn't be respawning in the middle of the map.
Trigger("Force 1"){
Conditions:
Deaths("Current Player", "Terran Marker", Exactly, 1);
Command("Force 1", "Torrasque (Ultralisk)", At least, 1);
Command("Current Player", "Torrasque (Ultralisk)", Exactly, 0);
Command("Current Player", "Protoss Probe", Exactly, 0);
Actions:
Preserve Trigger();
Set Deaths("Current Player", "Warp Gate", Set To, 1);
Set Deaths("Current Player", "Xel'Naga Temple", Set To, 0);
Create Unit with Properties("Current Player", "Protoss Probe", 1, "008", 1);
Display Text Message(Always Display, "You have been chosen as a Mouse. RUNN!!!");
Set Resources("Current Player", Set To, 12, ore);
}
This is the only trigger that makes invincible mice, so it's clearly running when your mouse dies. You need to add 1 or something to terran marker so that you don't make more than one thing.
In any case it's really hard to look at someone else's triggers and figure out exactly how they work with no background information, no concrete listing of the "problem" and what all the variables are.
IMO it's easiest to randomize a switch-> add 4 to DC if it's set, randomize that same switch again, add 2 to DC, randomize -> add 1. This gives you a number from 0 to 7 which you can then use to organize stuff.
For randomizing the cat for the round, assign the numbers to each player and repeat the randomization if they are not in the game. The sample trigger should look like this:
if
DC is exactly 5
Player 5 commands at least 1 building (or some other way to know that the player is in the game)
DC "randomize cat" is 1
then
this player is the cat, set a DC "is cat" or something.
set DC "randomize cat" to 0
repeat for all players, and have the triggers to randomize the switches/add to DC only run when "randomize cat" is 1. When the round is over and you're ready for a new cat, kill off all the units, set "is cat" to 0 for everyone and set "randomize cat" to 1. It will eventually find a cat for you.
In the same way, you can do "randomize arena", except you don't have to worry do much about leavers. Just repeat the randomization if the DC is 6 or 7 so you get a random number between 0 and 5.
Fix your randomizations and make sure your triggers which are only supposed to run once per round are truly running once per round by adding in a DC. Then we'll work on fixing the fact that your victory doesn't ever work.
"Parliamentary inquiry, Mr. Chairman - do we have to call the Gentleman a gentleman if he's not one?"