So here it is...sorry but I didn´t work with "DOS" for several years...
What... you don't use WinDOwS?
Um, the only thing I can see from a quick look is that you have a mod.ini file in your FS2 main directory. I'm not sure if that would cause a problem, though. (I don't believe it should.) Also of note, you have Fs1_port_3 . You should rename this directory to fsport , otherwise all the campaigns that use fsport in their mod.ini will not work. hip63 will have this issue resolved for v 2.0 of his DVD.
Does anyone else see anything with his install that could be causing a problem?