Well I've got it working, but I'm not sure if it's something I've caused or not!
The error looks like this:
Faulting application name: PixInsight.exe, version: 1.7.4.759, time stamp: 0x4efb56da
Faulting module name: vrfcore.dll, version: 4.1.1078.0, time stamp: 0x4b702b55
vrfcore.dll isn't part of PixInsight and is part of Application Verifier. I'm not sure if this is a standard part of windows, or if it came with Visual Studio, either way I don't use it. I fired up Application Verifier to see what it looked like, and surprisingly to me I found that PixInsight was selected. I unselected PixInsight closed Application Verifier and fired up PI. I noticed several things, firstly PI was much much faster, and secondly scipts work...
So personally things are now working, but I don't know if it's something I've caused or if somehow happened in the install process.
Adam