I´m using Joomla 1.5.15 with K2 v2.2. When create a new item from the backend and try to insert a ReadMore link then its go out from the article and go to the admin section homepage. I think that there's a conflict with the scripts used by K2 and TinyMCE.

I solved this problem using other editor, in this case, JCE 1.5.7