Some movement is normal, it goes through a flexible grommet, but the grommet can go hard and not seal very well. I pulled my valve out, cleaned up the mating surfaces and put it back in with a bit of RTV round it to make sure. You can get a new grommet but if you do watch out for the old one cracking when you try to get it out and bits of it dropping inside the rocker cover! The oil is normal AFAIK, it's condensate from the crank case fumes the PCV valve is designed to pass.