It has been reported that L3DT 2.2a and 2.2b tend to crash on Win2k machines. Another problem, which I fear is closely related, is that re-drawing of the active map may be skipped following some operations (eg exporting maps). At a guess I'd say these relate to the introduction of worker-threads in 2.2a. I'll take a crack at these problems when I get back from holidays.
Also, it looks like release 2.2b had a bug in the HTF-writing routine that caused random inversions of axes. For those concerned, a patched-up exe may be downloaded from here. This version also includes some minor changes intended for release 2.2c, for which I will write documentation at a later date.
I'm planning on releasing L3DT 2.2c in late Jan or early Feb, by which time I hope to have gathered up all the loose threads (sorry 'bout the pun). Until then, toodles.