My GOG downloader seems to work just fine, and I can even see the popup on my Windows 7 taskbar, but for some reason the actual window no longer appears on my desktop even when I click on it in the taskbar. Anyone else having this problem and perhaps a solution?

The downloader has been having issues all day today and yesterday as well. Things like you decribe seem new to me......but we've had downloads downloading corrupt files, DLs running at really slow speeds, downloads not starting at all, etc etc etc. I recommend just using your browser of choice to DL the files provided your connection is fast and reliable enough.

From what I remember Adobe AIR had an update yesterday or the day before that; you could try checking that you're running the latest AIR runtime which is 2.5.1 and if so reinstall the GOG Downloader.

If that doesn't fix it uninstall the downloader and then AIR followed by installing AIR again (get it from here) and then the GOG Downloader.

Unfortunately the whole window/window element not appearing tends to be an AIR issue (I've had to deal with it with other AIR based software as well) and at this current time haven't managed to track it's cause down.