After about two months of owning a MakerGear Mosaic, I had only one small issue. The guide rod that the Z-endstop is attached to could rotate freely, causing the endstop switch to move out of place with the vibrations of the printer. This is a simple modification to the original Z-endstop that ships with the Mosaic to keep the guide rod from rotating.This can either be printed as a support that fits between the switch and the existing endstop, or as an entire endstop (which I have not yet tried). I recommed the first option, as the support can be installed without much disassembly.To install the support: 1. Print 'mosaic-z-enstop-mod-support.stl'. 2. Unscrew and remove switch assembly from the ensdstop. The LED should pop right out with a push from below. 3. Unsolder wires from switch (don't forget where they go!), place switch on support and rewire the switch through the slot (see picture). 4. Screw switch and support to endstop, replacing LED in it's hole.If you feel the need to have the modified endstop as a single piece you can try printing 'mosaic-z-enstop-mod-endstop.stl'. I haven't printed it yet, but support material will certainly be required. You'll then probably need to take the printer apart a ways to install it. Also included is the OpenSCAD file that generated both stls, as well as the original Z-endtop file I got from here: https://github.com/MakerGear/Mosaic Thanks MakerGear!