No sound from Composer but OK with Player

Hi

Thanks for such a swift reply...now that is service. I really want this to work as I think the product is superb. I did get it playing, for some odd reason, it suddenly came on! then it just went off again, then came back with what seemed like stuck notes, or at least the software not sending the correct timings on note. The music vaguely sounded correct.
Going back into Notation Player and everything is fine.
I loaded the demo on another laptop and same problems.
I have other midi software (Band in a Box) and that plays with no problem at all.
I can't think it is my laptop, unless Composer requires far more processing power than Player, but that wouldn't fit with the time that it played OK.
Any further advice would be welcome. THe amazing thing, when it played, was that I could play my Saxophone with it after transposing the melody part, all the others fit. Awesome!! so I am desperate to get it working and buy the software.
Regards
Steve