I figured out how to transfer save files, if anyone still wants to do the succesion game thing:
1. If you're still playing DF, save and quit.
2. Go to this folder. If you changed the name or have a different version, the first part should be whatever you changed it to or downloaded.
df_27_169_33f\data\save\3. Find the appropriate region folder. If, when selecting a world to load, it says "region7" in the info area for that save, the region folder you need is region7.
4. Upload that region folder to your favorite file-hosting site.
5. Give the next player the link to the file.
6. The new owner of the save file then downloads it to
df_27_169_33f\data\save\ (or whatever), and continues the game.
I tested these steps (except for the last three) between two different versions, the newer version having no save files whatsoever, and it worked. I assume that the last three steps will work without testing.
According to
the download page, any game from sub-version A to sub-version F (the current one, released yesterday;) is compatible with any other version within that range; however, I suggest that if we decide to use the same version, F would be a good choice; according to
the Changelog, Toady finally fixed the damn "hey, let's channel out each other's floor" bug.