Since there are a number of Probotix owners on this forum, some may be interested in this Fusion 360 CAD model I did some time ago. I created it to use as a base for future upgrades/modifications to the original Probotix design (I know they have since fixed some of the deficiencies in this early design). My first improvement was a redesign of the Z assembly, documented in an earlier post, and to date, that's all I've done.
The Asteroid CAD files can be downloaded from GrabCad as well as a generic version of the updated Z assembly.
https://grabcad.com/library/probotix-asteroid-early-version-with-table-1
https://grabcad.com/library/z-axis-assembly-15mm-guide-rails-1