Hi,
a short update on this. The default supplied with GNUstep actually do
work and differentiate correctly between drag operation if using a US
style keyboard which has right and left alt. It does not work e.g. on
Italian or German keyboards which have Alt Gr, since Alt Gr is not Right
Alt.
It can be however remedied by changing the mapping using system
preferences or defaults as mentioned before. If available on your
keyboard, the extra command key can be used successfully.
GWorkspace has been cleaned up from the default assumption and now
should work well, branch has been merged yesterday.
Riccardo