same here, i updated the emulator to 29.3.2 (on B4A 9.50) and now i get a blank error message wen trying to start a a AVD.
Steps i tried:
1.) delete the .android folder = all my old AVD´s are gone, made a new one, again blank error message
2.) manually update SDK manager to 3.60 = no change, blank error message
3.) create new AVD = blank error message
The blank error message: