Just tried a few more channels,
I'm using the latest version of GX
Geexbox works fine every time
Mplayer CE - Black screens
Neogamma - Black screens
Dop-Ios loads but code dumps on exit
Homebrew Browser - Black screens
I had cioscorp installed, then proceeded to uninstall it, no effect on the channel loading. I've also tried a few different SD cards and booting off the usb drive with similar results. All these apps work fine from the homebrew channel.