Hello,

When you installed Event Calendar Pro did you enable it in your theme.skin file? I'm not sure what you mean by "full screen" but I assume that you mean you're having some display issues with the pro version and it seems most likely that would be caused by a skin issue. If it's not something simple like ECP not being configured in the theme.skin then I will need more information to help you properly, like knowing what skin(s) you're using and if you've added any custom CSS to your site that might cause the problem, etc.

Hope this helps