TinyMCE & IE & Moodle 2.5+ = terribly slow

Dear fellow Moodle users, I need your help again

I upgraded from 2.4 to 2.5 a month ago. Everything was fine, except that it took at least 15 seconds for the TinyMCE editor to load. Because it was already the end of the term I didn't took it as a serious problem, since I was planning to do a clean install in the summer anyway.

Now, that I've installed a clean 2.5+ I've got the problem back. I've done a small research and it seems that it only persist under Internet Explorer (Chrome works fine) and IF I have these plugins turned on:

CTRL+right click helper
image
moodlemedia
moodlenolink

When I turn them off, TinyMCE is as fast as it should be, but if I turn on ANY of them, TinyMCE will load as slow as a dead snail.

I know that in 2.5 TinyMCE version was changed to 3.5.8, is it possible to revert back to 3.5.7 without reinstalling moodle?

Thank you for any advice you can give me!

Márton