Marko
"RGB color adjustment has a "keep luma" option, so that only chroma is affected."

That moment doesn't work with selector (alpha). a "color shift" one as example. and - I can take a fancy for the suppressing/enhancing of some color and not only be shift it.

and too - I didn't a find color filter except "rgb correction" who can work with alpha channel (kdenlive). I can't select a certain color (selector) and after it change luma for it. filters of brightness can't work with alpha (selector).

I've checked "keep luma" on alpha controlled RGB adjustment, and it works here without problems. (Kdenlive 078, Open Suse 11.3)

I plan to add alpha control to more of the effects (at least brigtness, contrast, saturation and similar), but don't hold your breath... have a lot of other work currently, hopefully in the early summer, when I get "off the hook" a little...

There's also a moment. When You see at picture, so you watch the same color, but if you're beginning to play that film that moment of color is changed. (video out). An effect of angled colors.

Can't kdenlive play one frame? for example canopus edius plays one frame (a loop playing). So you watch a real colors, and not "picture" of another video out (the frozen frame (when the film is on pause).

Am I a meticulous man :(

A mirror of that one (avidemux) http://avidemux.org/admForum/viewtopic.php?id=4117

And... What about "beziér curves"? I have them in "my Kdenlive" 0.7.9 (from svn repo) and it look very very interesting (and very difficult to master). I saw it behaves in a "selective way"... Well, I just hope, in the next future, that someone will write something about it (a tutorial maybe). Granjow did a great job writing about the recent vectorscope, color correction, ecc.
Greetings from Italy
Ignazio

Right now the Rotoscoping effect just manipulates the alpha channel. There is still work to make it an easy-to-use filter mask. In the meantime, to do a manual filter mask, you can place the same clip on a track below the one to filter, put a Composite transition between the tracks, and add the Rotoscoping effect to the clip on top as well as any other effects you want. Finally, draw your rotoscope to limit the region and shape of the effects.