Thank you kind sir, but I think you forgot the global.rpgsave. Without this file, I don't think it's possible for us to load the saves (or if it's possible, please someone tell me)
If you dont have a global file, and your having trouble with any saves you download. Run the game then start a new game, save the game, then exit out of the game, reload it and try to load any save files. By doing this it creates a global file, allowing the game to recognize that there is in fact save files present in the save folder.
Its also important the save files have their proper name. Sometimes users who upload save files attach names to them. IE Frog.rppg, when it should be renamed file5. Or whatever number slot you want to use. If you are unsure of of how many slot numbers any game has, and or, your not sure of the save files proper names, easiest way to know is by starting a new game then save it, look into the save folder and you will see the name of the save file, RPG uses (depending on the version a dev uses) different named save files.
Ive used this technique and still do and it has worked, being compressed or not, that doesn't really matter, but sometimes compressed games have flaws/bugs that could cause issues.