There are 2 specific problems that I almost always run into when I attempt to run Unreal Tournament 2004 on Linux.
- No soound
- Libstdc++
I am keeping a note of these 2 here.
For no sound, just use "padsp ./ut2004"
And for Libstdc++, try installing the library through your distro's package manager. Example: "sudo pacman -S libstdc++5"