[Greasemonkey] Blogger/Technorati script failing

[John E. Simpson]

Have been using this script:
  http://z14.home.att.net/scripts/technorati_tags_wspaces.user.js
(Alters the Blogger posting form to allow easy addition of Technorati tags, including multi-word tags.)

Since new GM 0.5.1 "final" installed, it has stopped working. Actually, now the whole "manage user scripts/new user script" functionality seems busted.

For the "manage" feature, the screen shot is here:
   http://home.earthlink.net/~johnesimpson/images/gm_manageuserscripts.jpg
Note the blue area, top right. Clicking on the Add... button does absolutely nothing.

Trying to get to the Add feature by right-clicking in a browser window likewise does nothing.

If I load the script in the browser window and do Tools > Install This User Script, then hit the Add button, it seems to allow me to add the script. See:
   http://home.earthlink.net/~johnesimpson/images/gm_installuserscript1.jpg
and (note the strange blank blue area again):
   http://home.earthlink.net/~johnesimpson/images/gm_installuserscript2.jpg
But clicking on the OK button does nothing. Only way to get out of the second dialog box is to Cancel, after which, of course, the script is still uninstalled.

Have uninstalled and re-installed GM itself, have cleaned out the scripts folder and attempted to reinstall the script. I don't think it's the script because the problem seems to be the script installer in GM.

Using Firefox 1.06, if that makes a difference.

Any guesses?

Thanks,
JES