Hey Scott. Thanks for the note here, and for your interest in purchasing PRO. I’m sorry to hear about your frustrating experience with the free version thus far.
Realistically, it’d probably make sense to get whatever issues you’re encountering in TEC sorted before buying PRO. I say this because they are ultimately the same codebase – rather than being an entirely separate plugin, PRO is simply an add-on that extends the functionality of TEC. To that end, it’s likely that something broken in the free version would also be borked in PRO.
However, it sounds like what you’re facing might be a legitimate bug – we do a lot of our testing on the WordPress stock themes (Twenty Eleven through Twenty Fourteen) and if something is broken in one of those themes, we generally view that as a bug we want to patch ourselves. Have you posted about this on the WordPress.org forums for The Events Calendar (http://wordpress.org/support/plugin/the-events-calendar)? We’d definitely be down to try and get it sorted there if so, to give you full confidence before buying PRO.
Hope that helps. Let me know if it doesn’t, or if you have other questions here.