Sorry to bump this thread, but I've found some new info that can complete this guide.
I looked around on The Glue Factory site, where we got the LTB to X converter. There is a program called Blender that can import .X, and with certain plug-ins can export to .LTA. Then, there is a ModelEdit program for NOLF2, which can compress .LTA to .LTB, our key component. However, to install it, you have to own NOLF2 (No One Lives Forever 2). If anyone has it, please PM me and I'll send you the download for the ModelEdit software.