I have tried to install widgets from online with no success, they go to tmp file and die. I then tried downloading them and using the superkaramba option was able to only install one which was a skz file. Any of the tar.gz files were a complete bust even if claiming for kde 4. I am running a debian sid fully updated machine. Could it be I am missing an app or two or the widgets are not compiled in a form I can use?

Currently, ( even on my trunk system ) it claims errors when using Get Hot New Stuff to download Plasmoids. It does install them. You may wish to check that you have the appropriate script engines installed ( which I believe to be my problem )