Bug with KILL or is it me?

[Doomtrooper]

KILL says it will 'terminate ANOTHER exa in the same host as this exa'. This leads me to believe it will not target itself (unless it's the only one in the host?).
One of my levels I'm in an infinite loop with one exa writing to M register, and to clean up at the end I am moving another free exa into the same host and running KILL to attempt to halt the infinite loop exa.
This is working fine 100% of the time if I step through 1 click at a time. But when I use the fast forward it always hangs on the first pass in that cleanup step by not killing the infinite loop exa. It's either being affected by the KILL itself, or its throwing an error and halting too fast for me to see.
Any ideas?

[mala]

mhhh exas do not kill themselves if alone in a room, but they will terminate right after, if "kill" is their last command. If your M reading exa is always in the room, there should be no problem in killing it, but if it does self replicate, there's a chance that you end up killing the wrong target (if there are multiple targets, the target will be randomly chosen), failing to stop the endless loop