well it looks like a lzxd format with fixed lengths in the header per file record (or they're being padded the last few bits) but beyond that I wouldn't know but if they're fixed length it shouldn't be too hard to work out the components of the header just look at some of the files you have managed to extract and their containers.
lzxd isn't the same as lzx, your best bet is to compare it with an archive you've managed to extract and look at the properties of the files extracted compared with the header.
lzx delta I think it's actually called, originally a ms format for cab archives but the format isn't strict, so to really get a grasp of what the header contains you'll need some extracted files and the archive they came from LZX Delta Compression & Decompression.
That's the most recent documentation I can find on the format.
Last edited by barrybarryk; 02-14-2011 at 03:03 PMReason: Automerged Doublepost