Mine is also completely worthless after attempting the update. I've tried re-setting it up with no luck. When it gets to the last step, it will not connect to the wifi network, but the light just stays flickering. I guess I no longer have to worry…
The killer app is them actually getting the current functionality working as promised, and the battery life beyond a couple of days. I can't even use the current temperature sensor to monitor my wine cellar as it is right now.
I implemented this as well, but my twine only updates once, then not again until I reload rules (or change the batteries). I've logged a bug about this, but heard nothing (as usual).
Everyone who is having this problem, please log a ticket with help.supermechanical.com. I don't think they have the resources to monitor the forums, but I did get a prompt response from the help site [no solution yet, but a prompt response].
What channel ended up working for you? The wifi density in my area isn't too bad, so I have quite a bit of flexibility. Did you just keep trying different channels until it stopped kicking clients off the WLAN?