thanks for sharing your tools, in my spare time I made a real ulz compressor, is still not efficient as the namco's one but we'll get there soon.
you need at least python 3.2
Bear in mind that even with the most efficient tool you won't get an ulz file that has the same filesize as the original. If you change something the compressor will produce a completely different file.
I tested against my own decompressor, when I have time I'll provide binaries (so you don't have to install python) and optimize the algorithm.
The compressor needs some parameter to compress files, those parameters are the ulz type and the compression level, you can get those information with the "info" command.
You can get information form iso and BPB files too, thanks to orientalcomputer_01 for that
I've finally run some tests with your decompressor/recompressor and I have some feedback for you.
Tests for Radio chatter and briefing TIM files went through without a hitch, the compressed file sizes were excellent and the game ran like it normally would.
However, 0114/0005.ulz and TIMs for the titles in the Search menu do not work properly after recompressing. The game still runs and does not crash, a good sign, but the graphics themselves come out garbled and with crazy colors. 0114/0005.ulz when uncompressed is a BIN or DAT file that contains several TIMs inside, the Search titles are regular TIMs with just one image, single-layer.
0114/0005.ulz is the file that has that text that is still in Japanese in the current v2.0 patches, the one that causes the inter-mission text (save game prompt and "Data Swallow" at the bottom) to go from English to Japanese at the end of every mission. This and the Search titles are the only parts still left for us to fix and make a final 100% fan-translation possible.
I'm not sure if it's just me or if you also encountered this problem, I ran extensive tests just to make sure and these are my results. The fact that the game won't lock up or crash shows you're on the right track, I just don't know what's wrong with these particular files.