Topcoder Google calendar available from here is awesome. It includes all SRMs, marathon matches and everything you'll possibly ever need.

But I don't need these long marathon matches which occupy my Google calendar and mark the whole week as busy. I'd like to have a calendar where only SRMs and TCO events are included. Maybe, the beginning of new marathon match would be helpful too.

Do you know any of such calendars? Maybe it is possible to tweak the standard one? Or should I make this thing myself?