With the 3D map mod i had a horrible issue of not being able to load Solitude, the load screen would never end. Then when i teleported to the middle of skyrim, there were massive errors, LOD went crazy, chunks failed to load properly, the map had massive gaps in it etc.
Apparently there is a fix for it, by taking out some lines, but i cant really be bothered to find out. As cool as it was, it wasnt very useful.