UPDATE:
We’ve released a new update for the launcher today to fix some issues that occurred with the recent Launcher release on Tuesday 5/6.
For more information you can find check out the forums (Link Here)
5/9 Release Notes - Launcher version 1.2.1-2068268
–Bug Fixes–
Right-click uproject options do not work on Windows
Launcher becomes unresponsive when updating from 1.1.0-2054669 to 1.2.0-2064046 with UE_4.1 and all 4.1 samples downloaded