Re: FXB Conversion quality problems

Additional note: You asked about the Kaydara (animation only) (*.FBX) export
option.  This option was used a lot back in the days that MotionBuilder was
still owned by Kaydara.  That's not to say this option is no longer used,
however.  What this export option does is convert all objects into nulls/dummy
objects.  It attempts to retain all animation data, ensuring that the file size
is as small as possible.  No constraints are retained.  It's really just a bunch
of pointers that have animation data.  People would save to this format to
re-use within MotionBuilder ... but usually not within any other programs. 
Again, for interoperability, FBX Export in MB 7.5 Ext2 is your best bet.  Using
MB 6 Pro, your second best bet would be to save into the FBX file format and
import into Max (using the converter as an in-between option).  Since, in
MotionBuilder 7.5, you can save and load characters, "export animation
only" has become less of a valid option for retaining animation data, since
save/load character retains all character data and enables users to re-target
their animation data easily, as well.

Hope that helps.