Does installing preenv via the Need For Speed Undercover installer from extras-devel repository work for you (preenv is installed as one of the dependencies)?

Preenv appears to install fine for me using this method. The manual method through x-terminal failed for me.

I just didn't bother actually using the NFSUC installer as I just installed it for preenv.

Also, just a thought but make sure you got the extras-devel repository added to your app catalogue (at least until you've installed preenv after which you can disable it)