Hi,
to answer your questions:
1.what's the most common usage in the build project and car project situation ,3d warp or build in 3d max?
It depends on how complex the surface is. Some surfaces will be fine using the warper, others (like eg. the car) are done using 3D objects that will be adjusted then on site.
Please see these posts as well:
viewtopic.php?f=41&t=214&hilit=carviewtopic.php?f=2&t=429&p=852&hilit=car#p8522. i find that "before exporting .x file you will have to apply a material with a diffuse channel to the object so that PB can use this texture channel to map images on it."in the user manual. --what kind of the "material" for diffuse channel -a bmp or another ? and PB how to use this channel?
It does not matter which kind of material you choose - important is that you have the UVW-Mapping on your object. This mapping gives Pandoras Box the information how the Texture (=content loaded on the layer) will be mapped around the object.
Best regards,
Julia