Hello. Today I use the old Seminar for Joomla on a j 1.5 page. Works very well but i need to change to Joomla 3.
As I found your Matukio I think it looks like the Seminar for Joomla, but I have the following questions before I buy:

Can I make a "No thank you " button on front end (in every event, and I need to see who have said no)
Do the picture change when you have said yes to an event?

I dont use it as normal for events, but for internal people to show if the want to participate in an event or not. So dont use all payment feature etc.
Thanks

Poul