At the moment I'm not involved in any reenactment groups or events in any way. As far as I know, there are no Roman reenactment groups in Belgium at this time.
If someone in Belgium decides to start up such a group, I'll surely join. If nobody starts up a reenactment group, I will probably do so myself someday, but right now I just don't have time for it.
About the Roman calendar:
Based on info found on several websites en several of my books, and some translations in Latin I did myself, I've composed a calendar in iCal, the calendar application of Apple. I published the calendar on the web for others to view, and for other iCal users to subscribe to. I don't know which other PIM's can subscibe or download .ics-calendars too...
Feel free to use it in any way you want, and let me know if you find any mistakes or important holidays that are missing.
Bene vale!