I found a glitch on this. On any map, a random music brick appears in the ground right at the spawn point.
Eh...? It shouldn't be appearing. None of the maps I tested it in did one appear. Ah well, I'll upload a fix later. I know how to fix it, I just didn't do it before I release it since I couldn't find any errors with it. ("It" being a small function I added to preserve compatibility with some server add-ons.)
EDIT:
Uploaded a fix. Remember, this is a hacky (but convinient) way of making GUI, so it may have a few more bugs. Thanks Club559 for pointing out an obvious one which I missed.