Ha, I'm glad someone liked it. I stopped working on it because there was apparently no interest in further development. Even the raid group that was alpha-testing for me seems to have lost interest. I was motivated by the challenge of it, until I successfully proved the concept. After that, there didn't seem to be much point, so I kind of lost interest, too. I had big plans for it, though.
At some point I do want to make at least one more release, with the ability to load and save "slides" so you don't have to use the clunky import/export mechanism. And maybe some bug fixes. I won't promise anything, though -- it will be a result of a combination of circumstances, including: I have some free time, I am bored, and I can't think of anything better to do.
With regard to interior maps: Currently the plugin uses TerrainMap to get map images. So if TerrainMap doesn't work for that location, neither will this plugin. You can, however, find the asset IDs of interior maps manually, using Asset Browser or Image Resource Viewer, and add them to your blackboard as an image shape.