i tried the older driver version "WacomTablet_6.3.13w3.exe" too.
corel painter, photoshop and other apps work just fine.
Rats! They've only just fixing matching issues on the Mac side. Maybe it broke the Windows side in the process.
don´t know if it was introduced with this latest hotfix or if i was just lucky before.
ok someone told me to check if "use windows ink" is unchecked in the wacom settings.
when i installed the new driver this was on by default.
it made no difference earlier if i had that checked or not... but now it seems to have an influence.
the performance is still not perfect but the lag is much smaller after i unchecked "use windows ink".