Hey, I'm looking through bumpmap creation in the tutorials, but it looks as though the bumpmap is assigned to the mesh. I tried altering the assignment in CTU(from the original to a blank one because, honestly, I'm a noob for now), and I clicked commit but the bumpmap is still there. I went over a tutorial and it looks like I need to edit the assignment in Blender, but there are only instructions for Milkshape. Does anyone know what I would need to do in Blender?

CTU indeed has some quirks when it comes to editing the bumpmap, but the good part is that you don't need Blender to edit it.

What I recommend is getting all your images (base, specular, mask, bumpmap) ready, and using S3PE to replace the resources within the package. Simply right-click the image you wish to replace, select Replace..., and find your edited image. This way is easier and more practical in my opinion, because you are not restricted to keeping the same filename as the resource you edited (you would need to do this if you went the Resource \ Import \ From File... route).

I really do recommend using CTU only for editing presets. If you import images in it, they won't keep their resource name and will not replace the existing ones in the package, which means duplicate images if you don't delete the unedited versions.

I've honestly never tried making the bumpmap blank so I don't know what effect it has, but this bumpmap creation tutorial is very easy to follow.

I tried to do this but the normal map option is grayed out for me. Could it be that I only have a gray and alpha channel? (I messed up the order of the textures, so I think something was done wrong. I had to redo the base texture's details, and I completely and utterly forgot that color is done within the patterns on the first go)

To be able to use the NormalMapFilter, your image needs to have either 3 or 4 channels, yes. But I'm not sure I understand what you mean with the order of the textures? All the images you edit, except the RGB(A) mask and overlays (if you have any), should be black & white.

The order of the channels is:
Red - first channel in CAS.
Green - second channel in CAS.
Blue - third channel in CAS.
Alpha - fourth channel in CAS.

BUT you should not mess with the channels of the base, maybe except for the Alpha if you want to edit the transparent parts. It's the mask that you need to separate by channels. Every image should have at least the Red, Green and Blue channels and the mask generally has an Alpha channel as well. If you have a clothing item or object that has less than 3 recolorable channels, then the unused channels should be completely black on the mask i.e. completely transparent.

How many channels are you working with? Do you want to remove or add any?

Edit: to apply NormalMapFilter, you should also merge all your layers into one and have the RGB channel selected.

I had to take a break but I am looking through the tutorial for making a normal map further above and I am stuck. It states to copy and paste the channels, but it looks as though you can only duplicate after trying it in GIMP? I'm thinking when they mean paste there's steps I'm missing.

Nope, it's what the tutorial describes in the screenshots. You hit Ctrl-A to select the Red channel's contents (remember, now you're working with channels, not layers!), then select the Alpha channel in the panel, and paste the contents of the Red channel over it. Afterwards you select the contents of the Green channel and paste them over the Red and Blue channels, and you have your bumpmap.

I am not familiar with GIMP, can you post a screencap to show the Channels panel? (I'm assuming GIMP has this capability...)

Here's what it looks like.

I did a quick google search about gimp with copy and paste channels keywords but the results said nothing about directly pasting.

Oh, so it looks almost like Photoshop, good.

Like I said above:
- click on the Red channel in the panel, hit Ctrl-A, hit Ctrl-C (I assume "Channel to Selection" does the same thing);
- click on the Alpha channel in the panel, hit Ctrl-V;
- repeat above steps, only this time copy the contents of the Green channel over the Red and Blue ones.

Edit: by "click" I mean "left-click", not "right-click".

I tried to follow what you said but after using Ctrl V all options when right clicking a channel are grayed out. Ctrl A and Ctrl C also seem to do nothing.