Activation doesn't have anything to do with this. We don't change anything in the scenery depending on activation, other than not letting it disappear.
That seems more like a bug in your drivers or an undocumented tweak you applied. You don't say which sim you use but, assuming you use FSX, try to reset the FSX.CFG to default, by removing it, so FSX will create a new one using default settings.
Use ONLY the HIGHMEMFIX = 1 tweak, and nothing else.
And, after resetting the FSX.CFG, you will have to reinstall KCLT, because the installer will have to add its own Simobjectpaths lines to it, which were reset to default.
