Hey!
Thanks for playing the demo! As far as movement speed is concerned, I did increase it a lot more so it should feel better when I update it. Also, the Glider will now be tied to the jump button when in the air (no longer a separate button.) For the bug in the cave, I see that too and its fixed now, so in the next update, all the problems you listed SHOULD HOPEFULLY be fixed!
Other than that, thanks a ton for trying it out and providing feedback!
-R1GBY