My apologies, next time I post I'll be sure to put in all that information.
However, on this particular problem, I realized what the issue was... I hate to admit this, but in trying to switch from composite input to RGB, I was selecting the wrong input on my PVM. I actually cannot believe that I was that stupid, hahaha... that was several hours of troubleshooting down the drain because I apparently couldn't be bothered to double-check that I was on the right input!
In any case, thanks for your reply, but I managed to figure my stupidity out on my own!