Hi Dave!
Fitst of apology for the late reply, I managed to get it working by myself eventually. For some reason it started working after a few reboots. Which is strange, because why so sudden? The Main Sketch-Up help page opens in Google Chrome when I press F1. I also want to say that, when I had the problem there wasn't any case of the cursor not being in the active Sketch-Up window. I was'active in the Sketch-Up apllication, yet hitting shortcuts didnt work. Luckily it works fine now. This thread can be closed if you ask me
Best regards,
Sjotcher
(P.S. I completed my profile as well)