Yes. You can simply create a menu item to link to calendar layout of category view of the extension, choose the Category you want to display from menu parameter and then only events from that category will be displayed in the Calendar !
what I was hoping was to be able to have tabs / sliders with different calenders for different categories all on the same page - is there a module, or some other way the category calendar that can be replicated to achieve this?
As replied via Skype chat, there is not a module like that at the moment. In the future, I think I will develop a calendar module which allows you to display event calendar in a module and It will solve the problem. Might need 2 or 3 weeks for doing that !