finished the demo after around 3 hours of gameplay and experienced some bugs during my run but not that much. huge tip is to save often when for instance: walking long distances, after battling, before triggering events, etc. you are bound to encounter bugs that will require you to soft reboot and doing this will make your playthrough much more bearable.
some bugs that can be dealt with:
NOT LOADING (game stops to process): spamming inputs such as spamming enter and such can result the game freaking out and loading things too quickly, which makes the game not process properly. BE PATIENT AND DON'T SPAM!
INVISIBLE SPRITE: having a pokemon follower will sometimes make your pokemon sprite invisible, but as long as there's an HP bar you can keep playing and the sprite will reappear in the next fight. however sometimes both the sprite and HP bar do not appear meaning you are soft locked. RECOMMENDED: to not use follower for conveniency. also swapping pokemon will load their sprites.
FALLING OUT OF THE WORLD: sometimes when soft rebooting you may end up falling out of the world constantly when trying to soft reboot and get yourself out of it. THE FIX is to move (RUN) in any direction as soon as you click to soft reboot. also don't forget to save after you save yourself.
ITEMS NOT LOADED PROPERLY: items may confuse themselves and be read as something else. for instance a potion may actually be a revive and vice versa, and this applies for any healing item as far as I know. base the items on their DESCRIPTION and you can use them. if you got more bugs to share then feel free to drop them in the replies. I only know how to deal with the bugs that I encountered myself, so please if you got solutions then drop them too. I'm just saying that don't rely on me to solve issues that I never had to deal with because it's likely that I won't know how to.
here's my endgame team:
DEMO version 75