I've been in contact with David Taylor (author of WXtrack) and the full licensed product can indeed control frequency of SDR# allowing multiple satellites to be recorded unattended.
I currently have a working setup consisting of SDR# V1.0.0.1672, with the DDE tracking client plugin, talking to WXtrack successfully and decoding using WXtoImg. Windows 7 Professional. It seems that you can set WXtrack to control SDR# for *one* satellite, but ideally I'm looking for something to co...