PS1 platforming at its best!
Pros;
-fun gameplay very responsive controls
-excellent main character design
-trailing effect on ball is really cool
-the dojo entrance checkpoint is so creative, well done!
-fun secrets such as using attack before jumping makes you jump higher
-Its coming to switch? that's really hype!
-nice catchy music
improvements;
-your model A-poses in the bubble. Maybe it could rotate vertically like it's being spun, or a swimming idle animation?
-I collected all the letters from the stages, die once and I get a D rank, could you make it clear in an update how to get higher ranks?
-some background props could use some animation to breath life into a stage. for example, adding wind to the tress and parasols.
-stage names end in .nfv, I assume they're placeholder names or simulations in the story mode
Overall, this project looks very promising, keep up the great work!
As for your bug: have you tried the more current version 0.2.351-demo? The issue you had should be fixed in that build.