I got it to run on one of my other old PCs! I forgot that I had installed Direct X specifically to run an old DarkBasicPro game I made years ago. (It still failed. RIP Darkbasic games)
I really liked the art and design in your game. The bright saturated colors give it a unique feel. Made me think of Commander Keen 4 and other platformers I haven't played in a long time. The main character has a cute design. The overall gameplay was decent but...
...unfortunately, to echo some of the other comments in here, the controls did not work well for me. I immediately gave up on trees, and the lilypads were nearly the end of me. The double jump just didn't work consistently enough. I got to the boss, and gave up after two tries. Between his high health pool, small hit zone, and the jump problem, it seemed unlikely that I'd be able to win.
Still, it's good work and with some bug fixing and maybe a little balance update this could be really great!