Could you link the site? I'm not sure I understand.
Actually, don't link the site. I don't feel like dealing with viruses and malware again soon.
I've made custom sprites for RPG Maker before and I always found it to be a pain in the ass.
If you're creating GIFs, you can't add music to a GIF file. Unless you're talking about on the webpage itself?
It sounds like it would be a lot of work for anyone involved, including regular users. And also requires members to own RPG Maker, apparently?
If you're interested in creating a sprite based roleplay site, maybe find a programmer who could create a web-based sort of RPG Maker knock-off specifically for role playing (so without the extra world-building tools).
Then again, it sounds a lot easier to just go RP in a free MMORPG.