FreeLSS software lockups and other strange problems

I mentioned in other post that I'm having problems scanning in high res and with finer stepping (3200 steps per revolution).

At this moment, I'm trying to scan a 6" model of a pilot statuette.

When I scan it using the default resolution (1.9mp) @ 1600 steps, I get a fairly decent scan, not the best, but at least it's a start.  The PLY file size is 19.5MB

When I try to scan the same thing but using the high-res still mode (5mp) @ 1600 steps, I get a scan that is full of missing bands.  The PLY file size is 16.3MB

If I try to increase the number of steps to 3200, neither the 1.9MP nor the 5MP scans complete.  In fact they lock up during the left/right laser merging process at the end, and eventually require a power off and restart to get back into FreeLSS.

As a test I wanted to see what I get if I only do a partial scan, so I set the 1.9MP mode to 3200 steps, then set the range to only 90°.  It did complete, but it generated a 51MB PLY.  So I can only imagine this thing trying to work with what would end up being 200MB scans.  That's probably why it locks up.

The question though, is why is it generating such huge files??  By my logic, going from 1600 steps to 3200 should double up the number of points, hence the the file size should be about double, or about 40MB.

So what's going on here?