@dennisserras this is a bug in SG desktop, only started happening once SG switched to Autodesk ID.
V1.6.1 works. Alternatively, Patrick from SG support has a Python script that will bootstrap the authentication for you.
Some have also had luck with disabling GPU acceleration for QT:
https://community.shotgridsoftware.com/t/cannot-login-to-shotgrid-desktop/13063/23
Good luck!
-n