Sorry folks, I told people within Soartex that I'd be ready by December 20th. I was ready with the mod support at that time, but decided to wait until the 1.7.x Soartex was released and use that as the base for the 1.6.x FTB pack. I then started working on my own continuation of Soartex, and now I'm back to cleaning up just a tad bit of the mod support and releasing. The corrupted GUIs were a result of temporary file server problems, and they should be resolved now.
NocturneBlock added a few new Metallurgy textures,
Meara added a few new Tinker's textures and cleaned up some of my mess, and
ScottKillen worked on Engineer's Toolbox.
Updated FTB pack here:
http://new.creeperrepo.net/Soartex/modded/1.6.x/Soartex_FTB.zip
I used Soartex for 1.7 as a base and added in a few other mods, so you'll notice a slightly larger file size and more comprehensive vanilla support. This also means grass uses a standard greyscale base, which adds compatibility with grasses that are other colors than green (in exchange for a reduction of color depth). This will also work in 1.7, of course, if you're running a vanilla 1.7 instance.
Thank you SaintLucifer for your fixes and bug reports. Much appreciated!