Well I managed to make it work. Basically I unplugged stick, started ANTware II then plugged the stick back and from there everything was normal. Now I can start ANTware II without unplugging stick. Your "Ant+ Verification Tool" did not have this problem.
Funny thing is that in device manager device shows as following:
KP_PC
|
+--Atmel LibUSB-Win32 Devices
|
+--- ANT USB Stick2
I tried upgrading driver using "have disk" option and pointing
to the directory with drivers downloaded from your site but
it still shows under
Atmel LibUSB-Win32 Devices rather then just
LibUSB-Win32 Devices