When I add the motion->speed effect it displays in the preview and renders as just a grey screen like this:
[img width="720px"]https://midwestfishingadventures.com/sites/default/files/Screenshot%20-%2009162013%20-%2006%3A23%3A10%20AM.png[/img]

I using kdenlive 0.9.6 with mlt 0.8.8

I'm constantly seeing problems with the speed effect through all kdenlive official releases as well as svn bleeding packages up to this very moment. Either I get crashes, which are not reproducible, or corrupted output frames, or miscalculated clip snippet lengths and repeated final frames. Perosnally, I'm completely avoiding this effect as it is unusable. You may want to upgrade your mlt though, maybe you get more luck with it.

Hmm, just did a quick test with one clip, and motion->speed 133 both with stoboscope 1 and 9 rendered OK.
This is kdenlive 0.9.6 and melt 0.9.0 (openSUSE)

Set, for instance, to 200%. Render and thoroughly check, you'll find that there are repeated final frames. Also in kdenlive, moving the cursor forward and backward will cause diffent frames to be shown compared to directly placing the cursor at the same position within a clip with 200% effect. Also, sometimes frames get corrupted. It's still there with the latest sunab svn repo version.

Unfortunately everything I tried did not work. I had to use Open Shot to reverse, export and then import into kdenlive.

I'm also having problems whit this filter.

I have seen two behaviours so far.
I try t low down a part of a clip and What I get once rendered is either the time the part would have took as black or as the first frame.

It's a pity because I would say that this effect is a must for me (and a lot of people I guess)

Hope it is fixed soon.

Seeing only black or the first frame: I have had some good experience with remuxing the clip.
Rightclick the clip->transcode->remux with MKV.
Good luck!