How do I "update it"? There isn't a button for it in the game menu or on here.
Or do you mean, since the save data is located elsewhere, I just redownload it and overwrite the original copy, and it will still be able to access the save data?
Could I use other free software to create assets? Such as a free character model creator (seperate from RPG makers)? Also, since it's not being judged, could the music be arrangements of public domain music, such as Bach, Listz and the like?