Hello people.
I'm back from the pub.

Week off work.
Well many thanks again for your comments and testing, here's a few responses about what you've written.
Green Gandalf: U77 is installed over here, and I'm sure that's what I built the exe with, although I'm shortly going to recompile it, rebuild the installer, and replace the version on the website. I wonder if that is the problem, cos a while ago AVG was giving me false positives on exes which DB created. Seems to be fine since the U77 upgrade. Thanks for the comments about the graphics and sound, also. I am NOT a graphics guy and everything graphical takes me ages and multiple glasses of gin to satisfy my OCD

Thanks for testing it - wonder if you'll break it!
Phaelax: good luck with the spelling game!! I'd be interested to see how that turns out. Cheers for your positive comments.
MrValentine: As far as I know, I'm not trying to inject a PDF document into your system in any dodgy way.

Although the installer does contain the manual as a PDF. Wonder if that's what you're seeing.
LeeBamber: I am chuffed to bits that you like this.
mr Handy: Thanks for the Kaspersky report.
What a great community of helpful people we have here... your help and input is much appreciated.
James