Sorted!
Thanks Murphy. You inadvertently pointed me in the right direction. Looking at your post of the .ini file, I realised that this was different to what I was using. A bit of investigation later, I discovered that somehow I had been using version 2.5.0 of PSOUT and not the latest version 2.5.5. It would seem that the critical changes wer made in the last release.
All works fine now. What a great utility for some cheap training!
Thanks.
KC