We do actually display hints when you first load up the game. The first hint is an icon for the left mouse button when you havent dashed before and the second hint is an icon for right mouse button when you enter a puddle and havent pressed RMB (recharge) before. Maybe we should've made those a little more obvious (they are in the middle of the screen but maybe a brighter color?)
Regarding 1) I cant really say what causes this, but in my experience, this only appears the first time the game loads. Starting the game (or even the .exe a second time is way faster)
3) Yeah balancing might need to be adjusted. I think currently it is best if you play pretty agressive so you take out the enemies quickly.
Thanks a lot for the valuable feedback and playing!