ok, i figured it out,
the vnc-client must run on the PC, the vnc.oar just connects to it.
For all who have problems with the serial driver on windows:
i found this website:
and there i found code i put into an .inf and installed it to windows7 64 in my case after pressing F8 during boot and deselect driver authentification in the device-mager with add legacy driver.
Code for the Inf (win7 64bit):
%ProviderName%=DeviceList, NTx86, NTamd64
include = mdmcpq.inf
AddService = usbser, 0x00000002, LowerFilter_Service_Inst
; This adds the serial port property tab to the device properties dialog
ProviderName = "CDC Driver"
BfinCDC= "Blackfin Com Port"
ok i hope that helps, if someone wishes i could produce a little vid too, i think in such cases that would help a lot.