Okay, I've managed to extract the files from some of the JAM files (in this case, Billy.JAM) using QuickBMS, and while I still can't find anything that will read them, after digging around in Notepad++, I think I at least know what all the different files are actually for:
- .coo (coordinate/animation database)
- .emi (emitter files)
- .gro (group/box bounding geometry)
- .isv (geometry files - maybe)
- .gra (graph files, though these just appear to be databases for where the resources are loaded from)
- .mes (mesh files)
- .num (vfx/particle files)
- .rot (coordinate and animation files? According to most file extension websites this is the format Homeworld 2 by Sierra uses for its graphics, so it's possible they might share the same engine/format, though I doubt it)
- .seg (seems to refer to "segments" of the character, might be the bone file)
- .sha (shaders/textures)
- .sou (sound database)
- .sta (material files)
- .sur (surface texture)
- .tex (texture database)
- .wei ("weights", though it seems to actually refer to characters' mouths and eyes)
However, I'm at a loss for some of the other included file types: .ban (apparently "bank files", though I don't know what for), .dat (trying to open most of them in Notepad just gives me unreadable garbage), and .hvs (according to Google .hvs is used for 3D printers, so there's a slight chance they might be models or some other file relating to them).
If anyone would like to poke around the files I have them zipped here (sorry for all of them being "0000021" or whatever, but that's the name QuickBMS gave them):
http://www.mediafire.com/file/yvawvoa215...m.zip/file
As a closing note, someone was able to rip models from Charlie and the Chocolate Factory, which was made by High Voltage, so there definitely has to be
some way to get the models from their other games.
EDIT: Found more possible filetypes. Unfortunately at this rate it looks like the only way to get anything out of this game is to just straight-up learn programming.