I’m getting reports that Lancelot has a black border on some distributions - like in this picture: http://imagebin.ca/view/h1oGpJ.html.
If you have this problem, please file a bug report for the distribution you’re using. I’ve already sent a mail  to kde-packager mailing list, but it looks like some distributions’ packagers don’t really follow that list.
I don’t get why the kdeplasma-addons is compiled on a separate system (or virtual machine) compared to libplasma and plasma and with a different set of installed libraries.
 Hi all,
It have come to my attention that in some distributions (no need to specify which) Lancelot is compiled without the support for compositing while the plasma is composite-enabled. While compiling Lancelot, you should ensure the presence of libXcomposite, libXrender and libXdamage development files. Cheers and thanks in advance, Ivan