It doesn't seem to work correctly with conditions using "Each", "Everything" or "Anything". For example if I set the condition to be "Everything = 0", and I give it a signal, it still remains true.

Ugg, thanks. I'll open a ticket. Expect at least 2 weeks for me to get around to it.

OK. This is what I think I'm going to do (different than the other comment I just deleted):
Anything => Each signal compared to a constant (OR)
Everything => Each signal compared to a constant (AND)
Each => Each signal compared to its counterpart. True if Any condition is true (OR)

Doesn't seem like I can tap into the GUI components or standard circuit evaluation from the core so it won't be as clean as I'd like it but hopefully...

OK try it.