I try use version 0.7.7.1 installed from repository fedora 12 with all last updates.
When try view video in "monitor" window it looks bad (screenshot attached) and next time kdenlive crash with error "Fatal IO error 9 ...".
This behavior on different clip formats, but stop frames in monior window is ok.
mplayer play good this files vith xv and x11 option.

I googled similar bug descriptions, but no solved.
Can help me?

This problem looks similar to a problem we faced with version 1.2.13 of SDL on Ubuntu 9.10 with some X11 servers, and it is fixed in SDL version 1.2.14, available with Ubuntu 10.04. Please check your version of SDL on F12, and let us know. According to https://admin.fedoraproject.org/updates/SDL, F12 came with 1.2.13.

Oh - thank you very much, cause I forced install sudo rpm -Uh http://www.libsdl.org/release/SDL-1.2.14-1.i586.rpm and now have:
[vlav@homeserver ~]$ sudo yum list sdl
Installed:
SDL.i586 1.2.14-1 installed
Avialable:
SDL.i686 1.2.13-11.fc12 updates
Everything become fine!

SpecialNeeds, your problem is NOT the same. Your problem is that you are using Ogg Theora, which is known to be problematic. You need to transcode it to something else before trying to edit it in Kdenlive. Or, try Pitivi, which does support Ogg Theora quite well AFAIK.