Thanks for your reply. I am running Windows 7 32 bit, Dual Core 2.16GHZ with 4 GB Ram. I have installed the latest driver for the QX49. Everything works fine in Ableton Live Lite on the same laptop, so I don't think it is the Alesis keyboard causing the problem. I would prefer to be using Sequel 3, since I have paid for this version and it comes with so much more than I have with Ableton Live Lite. It just doesn't want to work for me...
Any help would be greatly appreciated.