For long this years on itchio people asked a lot for it, so its a licence that allows you almost everything if you mention me and link to the original files.

Jojo Jambo Jungle Sprite Pack. by DidiGameboy is licensed under CC BY-SA 4.0

This license requires that reusers give credit to the creator. It allows reusers to distribute, remix, adapt, and build upon the material in any medium or format, even for commercial purposes. If others remix, adapt, or build upon the material, they must license the modified material under identical terms.

Some poeple just took the demo and put on steam as it as even changing a single line. So, dont just do that. Putted the original code (gamemaker 1.3) to download. Paying for it you have musics and sound effects in gmx project.

Thats it! I want to remake this game someday if you support me. Have Good gamedev! Cya!