Just bought a Nano, very cute little fellow 
though I have problems to level the print bed to the Z axis, being to far of to the back and to tight in the front and on top of that it is worse off in the home position (far right in the back).
I have gone thru the two calibrations several times and also tightened all screws except the one’s that is to have some playroom but always get the same result.
I am to upgrade the firmware to the Marlin 2.0 (I think I saw a Nano edition mentioned in another post here but lost it) so perhaps the “auto” bed leveling calibration would solve the issue or is there any kind of mechanical adjustment that could solve this?
(Edit: I found the Marlin update: Updated firmware - Marlin 2.0.x - Vertex Nano - Whadda forum - Community Help and Support )