Multisite permalinks problem

Hello,
im using My Calendar plugin, which is really good thing and thank you!
My problem is, I have multisite web with sites based on subfolders. My main domain is http://www.ranapece.cz and subfolders for example http://www.ranapece.cz/brno.

I have central calendar on main domain and it shows all categories (all subsites). I have adjusted that one category is one subsite. For example: category “Brno” is for subsite “brno” – http://www.ranapece.cz/brno. Every subsite has calendar, but only with their category. So site http://www.ranapece.cz/brno has calendar which shows only “Brno” category. And every site has this setting. And it works fine! BUT…

When I add an event with category Brno, on the main calendar it works fine, but on the calendar on Brno site it has some different permalinks and shows nothing or bad site. For example on main calendar, the event has this link: http://www.ranapece.cz/mc-events/sdfgsdg/?mc_id=43 and on Brno site the same event has this link: http://www.ranapece.cz/brno/kalendar/?mc_id=43 so it doesnt work here.

Why is that? Same problem is when I add event on Brno site, so on Brno site it is going well, but on main site it has different link and has an error.

I tried different setting but nothing worked, even permalinks.

Thx and sorry for my bad English. 😉 My website is not running yet.