If you are having problems installing on Linux I may be able to help:

Email (forward) your invoice that you received from GOG to thehand@member.fsf.org (as well as a recent picture of you (attach)), as well as your name and phone number. Please  make sure  that the Subject of the email only contains your request for a UT2004 DVD ISO (be specific please, I get thousands of emails per week and if you are not specific your request may be accidentally deleted!).
You must provide said information in your emails (two: one, a copy of the invoice, and two, all of the other information).
I will then email you a link to an ISO of my Unreal Tournament 2004 DVD edition disc 1. (I bought it at Best Buy years ago.)
See here for proof (but I have lost the receipt since then):
https://docs.google.com/leaf?id=0B7w8KWMlJ2S-YWUwNGMzYWMtNDcxZS00ZWY5LTk2YzItOGJhN2M5NTE5NWVm&hl=en




I don't think that this would be illegal but if it is then please, one of the GOG.com staff please email me directly (you have my email) and *let me know why* (I will be happy to comply!).

Thanks gazhole for your instructions. I wanted to add for other users that for recent debian based distribution that use multiarch, the libraries are in “/usr/lib/x86_64-linux-gnu“.
I would also recommend using the package manager to have libstdc++5 rather than downloading a particular version with wget and installing it with dpkg.