The game has, afaik, seven different file formats for its data - .pss (cutscenes), .rel (I assume it indicates the properties of a level, since it has a couple of engine instructions), .inf (probably index files for its .wad counterparts), .wad (not same as Doom .wad, but is location for level data), .spb and .sph (found in PAL version of game, could be language differences given that there's one for every language [EN, FR, GE, IT, UK, SP]), .mib (disc streaming order files) - along with the usual, PS2 data files like .cnf, .irx, .img. SXXX_00.00.
What I'm interested in being able to extract, however, are just the .wad files. There seems to be some assets in there such as models (indicated by .inf files to be .MSH or .MSB), textures, scene data, menus, everything. Also, they're in general much larger than other files in this game, being at average 25 MB while other files are less than 5.
I have uploaded the .wad file for the first level (the clock) to a mega link, at https://mega.nz/#!D0JziSSB!w9JFCRqGooYe ... wEy9NH4RJ4 , because it is well above attachment limit.