Questions regarding textures in 3D Studio Max

[Lev]

Also, how would I go about doing a double-sided texture, like one texture on one side of a sign... and another texture on another sign.

There is a much easier way to do that - use a 2-sided material

1) open material editor
2) select a material slot and click on the material type button at the top (usually says Standard, Raytrace, etc)
3) Select Two-Sided from the list
4) assign the materials to each side

hope this helps