Trying to identify problem with long load times

Hi Guys, I wonder if someone could give some pointers to help track down an issue I have with some scenery i made.I have been using TileProxy generated scenery and saving it as permanent scenery. It has worked well and I have been doing the state of Wyoming. However during the scnery generation flights I was plagued with freezes and crashes, mostly referencing the gdiplus.dll. This only happened on the particular flight in question. Having covered the area and converted the scenery to permanent, by copying over the relavant .bgl files for the area into one folder (Scenery) and the texture files into another (texture), I found I still had the same problem when flying the permanent scenery. The other pointer to something being not right is the load times. This scenery takes up to 20 minutes to load, whereas my other sceneries of bigger size and made the same way load in a few minutes.The scenery uses the "old" system of .bmp texture images in the texture folder, rather than purely .bgl files. I feel that somehow the long load times and the crashes are connected, but dont know how. Do any of you scenery experts have any ideas? When the scenery was generated, no other scenery was in use.Cheers, Mark