you could try opening your .x model file in notepad and looking for lines similar to this
Material Material_0 {
1.000000; 1.000000; 1.000000;1.0;;
0.500000;
0.000000; 0.000000; 0.000000;;
0.0; 0.0; 0.0;;
TextureFilename {
"Treeagain_3.jpg";
and then changing the text within the quotation marks to the names of your textures, then just make sure they are in the same folder.
hope this helps.
Edit : sorry i didnt really read your post properly did i? sorry, i dont know much about the 3ds format, but yes they did seem to take longer when i was using darkgdk
void void void void void void void