It turns out I might’ve gone the long and hard route to install .NET. Since upgrading to wine 1.6 and using the latest winetricks
$ wget http://winetricks.org/winetricks
$ chmod +x winetricks
and using a clean WINEARCH=win32 prefix the install went a lot smoother.
$ export WINEARCH=win32
$ ./winetricks dotnet35sp1
initiates the install for .NET 2.0, 2.0sp2, 3.0 and 3.5sp1.
Unfortunately I have to go to this trouble as .NET 3.5 is a requirement for the installation of RMS Trimode and possibly Relay which is the sysop software for Winlink 2000 RMS servers. As I want to set up my station as an RMS mail relay this is very important. I want to evaluate the need and effective coverage of such a station with Winmor in South-Africa before even considering the huge expense of a Pactor 1-4 capable modem.
Having completed the above install of .NET I could install and run RMS Express without any trouble.
$ msiexec -i RMS\ Express\ Setup.msi
$ wine RMS\ Express.exe
Done and dusted. Now to get Trimode and Relay to work.