I don't think I've ever played anything in this genre before so the UI and control scheme felt very confusing to me at first. I only used the mouse though because I don't know the default RPGM controls either. But after clicking around wildly at everything I got the gist of it.
- No fullscreen option? Or option to increase the window size at least would be nice.
- The ally stopped at the entrance where the first skeletons are, I don't know if its intended or not.
- Opening the western most chest caused the one east of it to look like it was opened as well. But I could still go there and loot it.
- It doesn't seem all that interesting if you only have one unit, but I assume you'll have lots more later. So this would be an ok start.
- It seems a bit odd to me that you can't attack at all with a big mech if you break your weapon. I stopped playing while looking through the chests after a new weapon but got boxed in by enemies, whoops. I probably shouldn't have killed everything I saw I guess.
All in all it seems to work well and if you keep working on it could turn out good.