It doesn't matter which version you originally purchased, the online store is available to everyone
I suspect that this is one of two things:
Browser Settings
Screen Resolution
As for the latter, there was an issue reported a while ago with certain screen resolutions. The page wasn't visible as it should be (I'm not sure if this has been fixed yet). It may be an idea to check your browser settings, and even change resolutions if necessary, see if that solves the problem
Regards.
Carl.
Edit: Typo