Thanks for all the replies - I forgot to add that I had tried the exe on the Vista machine (bought Jan 08) first and it was fine. The laptop is a couple of years old with 768Mb, of which 128Mb is used for the graphics. I often run Photoshop, Faststone and Neat Image on it simultaneously with no problems and I have also run PowerPoint presentations with complex transitions and video, so I wasn't expecting serious issues when running a single exe. I have tried it on another XP desktop now and it nearly works; most of the transitions are there, but they are shorter than they should be and not smooth. So I have three PCs and three results; Desktop (Jan 08): Vista Dual core 2.3GHz 2GB RAM 128Mb graphics card – result OK, but some of the pans could be smoother Desktop (Jan 07): XP 2.9GHz 1Gb RAM 128Mb graphics card – All transitions present, but some curtailed and jerkier Laptop (Dec 05): XP 1.6GHz 768Mb RAM shared with 128Mb integrated graphics – All fading transitions missing except first and last ones, some other transitions missing, zooms and pans present but curtailed. So PTE does need a lot of resource to achieve its results. I have to say I am surprised that a 1.6Ghz machine even with an integrated graphics card can not handle the transitions, especially since a PowerPoint autorun slideshow can handle similar sized images and transitions with no problems – it doesn’t do the music, pan and zooms so well however and is difficult to synchronise. I will try downsizing the images that are not panned and zoomed and see if that makes a difference.