Hi, TJ.
Did you compared version number in DEMO and in Paid version? Demo is a newer version. Full version just not released yet.
Regarding zBrush and crashes… Using RC every day for more than 1 year. And did not have crashes even on more than 2000images and 600-800mln poly on my i7 6700/GTX960/64Gb.
Probably you tryied use raw billion poly mesh from RC, while you just need decimate it up to 10-20 times. And use 10-50Mln poly decimated mesh in work (it have enough details for 16K normal texture for 3-4m tall object). More poly is just a noise on normal maps.
Regarding deleting points. RC did not use dense cloud as it used in obsolete software. So editing of dense cloud just not possible. This is internal data, that not a “human readable” and “dirty”. Mesh is final and “cleaned” data.
But if you want reconstruct only required part. You can use masks. Tiff+alpha channel as mask. Or just fill unneeded part on images with uniform color. In this case RC will not calculate not depths not points not mesh in masked area.