i've been to autscape before (actually i've been to all of them), i'll try and write a bit about it but i am finding this thread overwhelming (and wp in general) so please dont ask me lots of questions! i've never been one of the organisers but have known many of them a long time, i guess it all dates back to about 1997 and some of the first autism / AS message boards and email lists on the net. ever since then we'd all wanted to have some sort of european autism event, it just took until 2005 to actually happen.
people there are generally high functioning to very high functioning (i say that relative to the obvious problem that there's no meaningful way to categorise and classify functioningness anyway - this is even more obvious at autscape!). the first year some of us were lower-functioning but they seem to have given up and by last year i felt like lowest functioning person there, i did miss them. i think it's true to say that the organisers would like to have more of a fair spread of functioning levels, but i don't think anyone knows how to do it, and it might require funding. so for now theres a strong highly-functioning bias.
there's talks and presentations in the morning/afternoon, discussion groups in the afternoon/evening, on autism-related issues, usually practical ones. in the evenings its a bit random, sometimes there's dvds on, often autism related again (eg mozart and the whale). though once there was a star trek evening, and a doctor who evening, you never quite know what to expect!
if you enjoy academic conferences, or religious retreats, you'll like autscape. or if you are the sort of person who finds there own way to enjoy things and makes their own holiday, its good for that. if you want drinking and entertainment and pre-packaged fun it's probably not your sort of thing. if you are seriously thinking of arranging a meet up then it's worth going just to see what it's like, and to copy some ideas. you might in particular want to copy the coloured badge system, there's probably details of it on the website somewhere.