Well done on getting the project completed for the IGMC jam :) Some mapping errors once you leave that first area that you might want to look at a little more closely, but the biggest issue was probably the fact that a guard gives you a key, yet it isn't actually added to your inventory. Sadly, as a result of this, I could not progress through that large locked door.
The battles were balanced and it was good that they were optional. The sound balancing needed addressing - this is kinda a problem with RM anyway, but you basically need to lower those levels on the music and sound effects (especially for battles!) otherwise it's just super loud. I felt like even with 'dash' (holding down Shift), I was quite slow - so if that's the speed you want your player moving at, I'd suggest making the maps just a bit smaller. The larger the maps, the more work you have to put into making those areas interesting and more detailed. So if mapping isn't your strong point for the time being (it is not my strong point, either) - keep things simple :)
Hope you continue either this project or making games and submitting to jams!!