Yes, that's where the FILES need to go. There shouldn't be any folder named ChikasFireV0201 - if you're seeing one with your unzip software, open it up and extract the files inside of it directly into the game folder.
If you unzip it to the right place, your operating system / unzip software should ask you "Do you really want to overwrite these twenty-something files?". That's the key - it needs to overwrite some of the baseline FillMeUp stuff or else the ending material never sees it's trigger conditions.
What you did, unzipping so the files are in the game's folder tree but not replacing the original stuff, just confuses the game - there are a lot of places where two copies of the same information exist, and it doesn't know which to go with. That's what your previous error was all about.
For this to work :
- You can't have that second set of files. That'll always throw error messages, even if you do everything else correctly. I'd recommend deleting everything and starting again from scratch.
- When you unzip Chika's Fire, after unzipping Fill Me Up, you have to drop the files such that all of the non-image files land in the /game directory and overwrite existing files.