The FM V-Towns is a higher spec version of the FM-Towns. Probably best to try to get the simpler systems done first, I think
Anyway, I think I've done all I can for the Towns driver for now, since i386 protected mode bugs are making more of an impact now. It's impossible to call interrupts in protected mode since the vector addresses are 8 bytes long, and the MAME i386 core treats them as 4 bytes each, thusly calling the wrong vector. It does at least use the IDT, I suppose that's something.
Also, the I/O priviledge level and nested task flags can't be set. Damn shame that the Towns version of MS-DOS requires protected mode, I was hoping that it didn't.