As for the impression of emptyness: True, three exhibitors we were used to see there (Desk, MicroDigital and Uffenkamp) were absent. But on the other hand I think CJE, hubersn and Spellings were new to this show so that the number of exhibitors was unchanged.
But as for visitors at the beginning it was very empty - AFAIR last year the show started at 11h to allow for longer distance driving there. We got there about 45 minutes later than I expected due to traffic jam near Uetrecht - one highway exit for Uetrecht was closed if I understood the Dutch signs correct. I guess we made it shortly before 11h since I was early on the road and we decided to leave the highway near Uetrecht and use smaller roads for some time. It does pay to have a local map with you ... But it does have some advantages that the show wasn't as crowded (though as time passed by the number of visitors did increase) since it was easier to get the chance for a chat with the exhibitors.
As for RiScript I learned that one of the two authors moved and now the two don't live as close to each other anymore. This move is the reason for some delay, I was given to understand.
As for Castles presentation: I do remember the odd other issue they talked about like ipSign, USB/USB2, RISC OS 5, Oregano 3, etc. - I didn't have the impression that they focussed on DVD and C/C++.
As for the A9home: There was one of those on the end of the CJE stand (they sell them) and you could see the nice transport case for it too. But it is indeed so small that you barely see it.
Overall I'm happy I opted for a drive of close to 500km to the show (and the same back again).