I made a small demo listing, that'll hopefully make demo playing more convenient until id releases something nicer!
I just made it very simple, a list and a play button, nothing more.. It's not supposed to be a replacement for anything, just a temporary solution :)
it's added to the right-hand side of the site when you enable the extension.

You can download it here, www.zanmato.se/download/qldl_1.4.2.xpi
Hopefully it'll work for everyone!


I had to make it an extension since GM scripts do not allow access to the local filesystem.

Installation

Firefox
Click the link, firefox should ask you if you want to install it.
Otherwise download the file and drag & drop it on to a firefox window. If id doesn't add something to replace this soon I'll add the update stuff so you won't have to download a new file every time.

Prism
Three options!
1) If you have the statusbar enabled you can go to Tools > addons and drag the file onto the addon area to install.
2) Install it in firefox and go to your Firefox profile folder, in %appdata%\Mozilla\Firefox\Profiles\<yourprofile>\extensions\ and copy z at zanmato.se to %appdata%\Prism\<whatever you named QL>\Profiles\<yourprofile\extensions\ ... Done!
3) Unpack the xpi and put it in the prism extensions path.


Updated
1.4.2
* Added Prism support
* Removed all the unnecessary gm stuff

1.4
* Added 'Config' option, click to find the config you want to exec before the demo
* Added 'Sort by name/time' simply click to re-sort
* Added Prism to the list of target applications, installing works. Haven't tried if it works inside QL..

* Fixed NS_ERROR_FILE_NOT_DIRECTORY bug
* Added refresh link, this will refresh your demo list
* Fixed the duplication bug
* Fixed bug with deep nested demos that couldn't be played
* Added preference pane, if you get errors then add the path manually in the settings (Add-ons > QL Demo List > Settings)
* Looks for demo folder in AppData (thanks exoQue!) doesn't work in vista/win7 so still looks from the Home folder as well. Falls back on registry.
* Looks for demos recursively
* updated it to look for the XP path if it can't find QL in the vista/win7 style path