Any help would be appreciated.

Have you let the installer run a self check? I have installed The Witcher 2 without any problems, but I did encounter broken installer downloads from GOG. In that case you might need to re-download the part which is corrupted.

Unfortunately I've tried this.

Well, it's a 1GB file inside a 16GB installer (which is broken into 13 pieces)... so my best bet would still be to re-download :(

I understand, but I've already tried this.

Already redownloaded and reinstalled once. Not doing it again, as it isn't a solution.

Any proposed solutions out there?

Would appreciate help.

Here is my theory:

GOG downloader was downloading penumbra and witcher 2. When my computer crashed recently something became corrupted, likely the GOG downloader's own cookies or whatever it uses to keep track of downloads and stuff. Penumbra is listed as being downloaded whenever the downloader opens.

I have uninstalled the witcher 2, GOG downloader, the entire .exe archive, and then restarted my computer. Upon reinstalling the downloader Penumbra is still listed as almost being completely downloaded even though there is 0Kb of data at the setup archive. This leads me to believe that whatever has prevented the witcher 2 from downloading properly through the downloader will continue to happen so long as penumbra is falsely listed as being downloaded.

At this point it's about getting the downloader working. I could probably get witcher 2 to work if I downloaded it without the GOGDWNLDR, but I want to get it to work as well.

So if it involves going into the registry or deleting something else I don't know the location of I'd greatly appreciate how and where to do so.