Hello,
just in case anybody runs into this: According to NX there seems to be a bug an VMTools 8.6.0 which are shiped with ESXi5. After installing/upgrading to 8.6.0 the NX-desktop may hang or not respond to user input.
http://www.nomachine.com/ar/view.php?ar_id=AR11I00608
The workaround in this link works (at least in my environment).
It also seems (again at least in my environment) that VMs after updating to 8.6.0 can have problems with the GNOME-Desktop (after logging in to the GNOME-Desktop the mouse pointer is in "please wait"-mode forever). It seems the remocal of the previous version of VMTools has some problems with restoring vmwlegacy_drv.so. So ln -s /usr/lib64/xorg/modules/drivers/vmwlegacy_drv.so.old.0 /usr/lib64/xorg/modules/drivers/vmwlegacy_drv.so solves the issue in this case.
cheers Christoph