I'm wondering if it is possible to install 2 different versions of Decoder Pro in my computer. I have a Digitrax PR4 which is running OK at the moment. It has the limitation of not being able to run a loco up and down the programming track so I'm never really sure if the loco is actually running properly. The PR4 is attached to its own length of track. I also have a Sprog 2 V3. It is not working currently as it has suddenly decided it cannot connect to when starting up Decoder Pro. The Sprog is attached to its own length of track. I want this to work so I can program locos and actually run them up and down the track. When I used to connect the PR4 or the Sprog I would always get an error message regarding whichever one wasn't connected. Now the Sprog has an error message whether its connected or not. Can I install 2 seperate instances of Decoder Pro and set one up with the PR4 and one with the Sprog 2 ?