In case someone else has the same problem…I was about to ask about it, but figured it out:
I was so frustrated last night after I created a model, finally learned how to UVMap in Blender, created the textures (in The GIMP), and tried to load it into the test…only to find that my model wasn't visible at all! I was shown that there were vertices, faces, and a mesh, but everything was black! After playing with the md5mesh file in an attempt to solve the problem, I sat it aside for the night.
Today I found out the source of the problem: me, being not so familiar with TGA and The GIMP, had left RLE compression on (a default setting in The GIMP). Once I turned that off and re-saved the texture, everything was fine!
EDIT: Remember to always do "Save-As" and disable the compression, as when you load the TGA image it will most likely still be set by default.
I didn't see something similar on the rest of the forums, but the topic may exist (or maybe it's just such a noobish question it's not necessary ) In any case, hope it helps someone!