Ok, I have NEVER figured out how to apply a texture to only one side of a brush... how is this possible?

If you are using hammer simply press Shift+A. This opens a new window, here you can choose which texture to apply and how the texture will be scaled.

But... when I click on a face it selects the ENTIRE brush... 0o"


ALso, how do I un-group things that are grouped when I've saved and closed the map, then re-opened it, with them grouped? It doesn't seem to let me do that...

You have to use a certain tool in order to select individual faces. Once you activate this tool, its window with all the face properties must remain open or it will deactivate automatically.

I attached an image to show what the button looks like in VHE.

Once you have that tool open you may now click on seperate faces and adjust the textures there.

Once grouped you just do the same process as grouping except you choose ungroup. Is it possible that you grouped it more then once? If you did then it acts like a stack, where the groups build on top of eachother. Try selecting the objects and using the ungroup command 4-5 times and see if it works.