If statement closes batch

I have almost no clue as to why this shouldn't work. I've tried it multiple times using the same syntax, but now it just closes the window. Doesn't even tell me the dreaded "if was unexpected at this time". It just closes. This is what I did.

Setlocal EnableDelayedExpansion
:debug1
set /p debug1=: 
if !debug1!==write (
    rem code goes here
) ELSE (
    goto debug1
)

As you can tell, this is a normal way of making user interactivity, and I've used it before, too.

I suspect this might have something to do with the program as a whole instead of just this little example. So you can download the program here, if that's your thing.

Thanks in advance.