I have the 3.31 version. I tried all 3 different link options for the new vesion (full, update only, and compressed). When I tried to drag my save folder to the full new version folder it says the file is too big and needs more disk space,
Do you have free disk space?
the update version lets me drag everything (save, patch, decensor) to the v3.41 folder but when I open the game it gives an image error and never gets to the main menu,
You don't use the update by itself. You have to copy the files from the update into your 3.31 and overwrite every things. Your save will still be there, so no need to move it. Just make sure you copy the update correctly.
the compress version doesn't let me drag the save folder to the v3.41 either (gives another error).
I have never used the compress. However, the file structure should be the same. I think you ran out of disk space, or the folder may be read only.
I could of sworn there was a different method of using/dragging files with the "update only" download method but I can't remember. It sounds like I drag certain files from the "update only" V3.41 partial download into my previous full version, which is V3.31. But I can't figure out what exactly. Any ideas?
If you know how to merge two folders, just merge the update with 3.31. Overwrite old files with newer files.
For Windows 10/11: the trick is just rename the two folder to have the same name, but in different places. After that, move the update into the same place as the old 3.31. Windows 10/11 will perform a merge. Overwrite old files with newer files.
Alternately, you can copy the files manually for each directory. Overwrite the old files with newer files.