Tom,
I use nothing but Firefox, you are preaching to the converted here

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I hope Bill Gates or any of his supporters does not see this interaction, though, because right after reading your message it occurred to me to try and download
the Flash based themes with IE (I haven't uninstalled it from my computer because sometimes it becomes necessary) to see if I also had a problem.
Well, I hate to say this, because I'm definitely a supporter of the Mozilla initiative, but I downloaded the file without any problems with IE.
I've tried again with Firefox without success. The file does seem to be downloaded, but when I try to open the zip archive, I get the message "Cannot open file: it does not appear to be a valid archive".
This doesn't mean that the source of the problem is Firefox, because obviously many of you are able to download attachments from the forums without any problems with this browser. But I must have something in my configuration (I cannot really figure out where) that makes the combination of Firefox and files attached to forums a bad one (I have no problems downloading files outside Moodle). I've had other strange problems with Firefox in Moodle that I'm unable to explain, like the fact that in my Moodle site I cannot use the winking smilie in the Moodle HTML editor.
Anyway, in spite of my problems, the advice is good and I keep on giving it myself

In the moodle.org site, the winking smiley obviously works, so it is clearly not a problem with Firefox in general, but I do have a problem with MY Firefox or with some other part of the software installed in my computer. Maybe it is time for that horrendous reformat and reinstall

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By the way, Rene, cool site! Perhaps you could explain what you did to adjust it. It looks even better than the original.
Josep M.