That's generally a good approach. The most important for people reading your story is to identify the places they read about on the map. Then you can expand on it later with more names if you write more stories set in that location.

The ".png.bmp" filename is part of the process. If you see a file with this ending, it basically just means the export crashed halfway through.

Basically, what happens is that CC3+ needs to render the entire map before it can be converted to png, it cannot simply be exported straight to png or jpg, and the native format of windows is BMP. So what it does is that it always exports the file to .bmp first (this is the map.png.bmp file), and then at the end converts it to png (or jpeg) which results in a new file, map.png, and then the original bitmap file (map.png.bmp) is deleted. But if this file is still around, it usually means CC3+ crashed during the export so it never got to the conversion and deletion steps.

Do the crash only happens when you go up to 9000x9000? I see you mention 6000x6000 being to small, so I assume that one actually exported?

This is an issue with the old FT3 that is fixed in the newer FT 3.5.

The issue is that FT3 saves its settings in the program directory, which windows only allows if you run the program as administrator (Right click the shortcut -> Run as administrator)

By default, templates only contain references to the fills used for the style (You REALLY don't want to have them all listed, trust me :)), so that means that drawing tools not made for the current map style will show up using the currently selected fill (see your status bar), instead of the actual fill used by that tool in it's native environment. (Your current map seems to be the Ancient Tombs style)

There's more information in this FAQ topic, including how to import the fills to the current template:

Sorry to hear you have so much troubles, but hopefully you'll manage to sort it out.

When you say wiped 40% of your map, make sure to check out things like sheets and sheet order. You may end up with something on an unexpected sheet after ungrouping, which means things may just be hiding out under something, like below instead of above your landmass or other terrain.