Couldn't really say for sure... it is a bit of a weird setup. Component mode (F8) seems to be slightly different than the RMB component selection. E.g. If you RMB to vertices, you'll have to hit F8 twice to get back to object mode. Once to really go into component mode and once to get back to object. I wonder if it's something like a local and global effect. Anyway, hope that's working for you now. It's really an odd thing.