Artifacts when entering a map

[JAsmine-ja2 NA]

Sometimes, when entering a map via "merc placement" (before a battle), there are "artifacts" present on the map. Mostly lights (maybe from break lights), sometimes patches of gas (tear/smoke). Here is an example:

Note, that I've not entered the sector before in this campaign. Also, I'm entering from the north and the light is somewhere in the south. When I save the game (after merc placement) and then quit and load again, the light is gone.

This has happened at least 3 times in my running campaign. I have not yet made out a pattern behind this...

Forgot to mention: It's v0.12.189 with 800x600 resolution.

[JAsmine-ja2 NA]

Another example for this issue:

Again, the map is entered for the first time. The lights really shouldn't be there. This time, it seems like the issue remains and can be seen in a savegame. Just load it, compress time, enter the battle and you'll see the "artifact" light.