1. I currently use "bobs tools" in the plug-in section to make stairs and it uses caulk on certain side of the stairs (im guessing to increase speed of the map) and the when it uses the caulk I get a "shader not found" brush -is this normal for caulk or should I be getting a brush that says caulk (like the sky brush)?
2. I have tried to join two brushes in the past and I get "cannot add brushes with a concave hull" error -What exactly does this mean and is there a way around it?
3. Is there an eay way to make a triangular roof as in a house or do I have to stretch the verticesand hope I can make it even?
4. I have the GIMP for imaging( www.gimp.org ) Is this sufficiant for making textures (I cant afford PSP or photoshop ) and how exactly do I go about doing it? Im thinking pixel by pixel but some of the games textures look pretty impressive and I thought maybe they used some special program to make it. Maybe a few pointers from you more experienced guys/gals out there?
5. I read somewhere that CSG subtract can cause poroblems with maps its used it on ( I currently use it to add posters/decals to various parts of the map) what kind of problems can it cause and would there be a better way to add decals without getting that "see-thru" effect that overlapping brushes causes?

Hope that wasnt to much for y'all and thanks for any help anyone has :)

4.

The GIMP should be just fine. The textures need to be in 'squares', or like, of a certain size like 256x256, or 512x512, 256x512, etc. While some textures might be created by hand, I'm sure that some of them are touched up digital photographs, or created by other software that generates textures or surfaces.

5.

Yeah, using subtract like that is a bad idea. If you want to make a decal, try doing this instead:

Make a brush with the 'no draw' texture. Make it only one unit thick, and of the dimensions of your decal. Put the decal on the side that you'd see, and now place the decal just in front of the wall or surface that you want it to 'appear' on. The 1 unit isn't far enough for the player to notice. You could also use somthing solid and make the edges beveled so folks don't get 'stuck' on it.

1. caulk is available the same as the sky texture. It's in the tools texture set.

2. Why are all brushes considered to be convex rather then concave? Let's compare a brush and the cutting tool to a block of cheese and long knife that can only extend past each end of the cheese. You would find it impossible to cut a "dent into the cheese since there is no way to cut peices out of only the center. You can only cut shapes that are equal to a flat plane. Two flat planes could be cut to create a convex shape, but not visa versa. This is why all brushes are considered to be convex rather then concave.

3. you can define the number of side when creating a. Arbitrary Sided Brush (in the menu) but you still have to drag vertices to make it fit your building. Dragging vertices can be exact if you just count your grid lines as you drag.

Thanks for the replys -espically on the whole brush merge -I kinda see things in a whole new light now :)