They work for me but had contact with Valve about it... They're willing to fix it but have a hard time doing so,
I haven't been able to reproduce the problem here. I've contacted a couple of the people who emailed us directly about it and asked them for more information. If you know someone who is having this problem please have them send me their system specs and the path where they have Steam installed on their machine so we can try to figure out what's happening. Also, if they have a sample .dem file that's failing have them send that, too (if it's not too big).
Anyone? Just reply here and I'll copy paste.