I'm the guy who asked a question at EE@StackExchange recently. I do interested in such professional open software like Sigrok. I'm not trying to blame without a reason.

First, of all, why the software isn't able to to show me only the rates supported? Ok, may be there is no such mechanism to determine it...
Anyway, I have choosen 1 MHz and 1M sample. It IS supported. And it works... first time. If I hit "Run" again, it shows me the dialog I've mentioned, no matter what rate I choose.
But after all, I can't trust software that crashes with segfault when I hit "OK" in Connect to device dialog. Fortunately, it is possible to select device from drop-down list on the panel.

I got up-to date openSUSE 12.3 x86 with KDE. I can provide more info if you need one to investigate the issue. 

Regards, Ilya

P.S. I have reprogrammed the device into Saleae Logic by now, but simptoms are the same