Strangest thing, but, if I put debug.print statements in my code, they
simply get ignored when I run the project. Also, if I try to put a
breakpoint on a line containing debug.print, it jumps down to the next
available line of code when I run the project (or jumps down
immediately if the project is already running).

Another thing that's stopped working is the gray highlighting that
shows which blocks of code were played prior to the current one. Now
it's very difficult to answer questions like "who called this function
in the first place?"

The only thing I can think that could have caused these problems is
that I've added an installer to my solution (so the solution now
contains one main project and one installer project).

Ideas/suggestion/help greatly appreciated.

-Dan