Hello Blkbird 
Regarding the encampments bug, I may be able to fix it but I cannot promise it. The fog management in civ5 is full of loopholes and weird side effects, like the one you observed.
Regarding the options you asked for:
* Show encampments is not possible: encampments are not generated by the map script, instead they're dynamically generated by the game on every turn. So there would be no encampment to show.
* Show ruins is definitely possible, it is a good idea.
* Show improvements is possible but what's the point since map scripts do not generate improvements (aside of ruins - they actually are improvements).

Regarding the encampments bug, I may be able to fix it but I cannot promise it. The fog management in civ5 is full of loopholes and weird side effects, like the one you observed.
Regarding the options you asked for:
* Show encampments is not possible: encampments are not generated by the map script, instead they're dynamically generated by the game on every turn. So there would be no encampment to show.
* Show ruins is definitely possible, it is a good idea.
* Show improvements is possible but what's the point since map scripts do not generate improvements (aside of ruins - they actually are improvements).