Electrum Beta 2.0 binaries out:
https://electrum.org/beta/ for those you want to use the Trezor without compiling software or using mytrezor.com
I downloaded the Windows .exe file. It ran on my Windows 7 system, but when it came across the Trezor wallet file that had been working with a build of an earlier version, it choked. So I removed the Trezor wallet file and restarted the .exe. This time it gave me the "create wallet" dialog, but this dialog did not include a decision box for "hardware wallet" which the earlier build did have. So apparently this beta .exe file does not include Trezor support.
Not sure if that's it, but can you check wether the trezor plugin is enabled in tools / plugins?
The Trezor plug in is listed, but it is greyed out. This was true without a Trezor connected. I exited the program and connected my Trezor and repeated the test. Again, the Trezor plug in was greyed out.
I note that the older version of Electrum 2.0 that I built from source had similar behavior. If a non-Trezor wallet was restored from seed, the Trezor plugin was greyed out. Apparently, the only way to get the Trezor plug in menue non-greyed out is to have already created a Trezor wallet, which I did using the initial Wallet Creation/Recovery screeen. Unfortunately, I was unable to do this with your .exe file since the Creation/Recovery screen didn't list a hardware wallet option. One further piece of information: the Create/Recovery dialog with the older source file build includes the hardware wallet entry, even when starting without an Electrum directory in my App Data \ Roaming folder.
If I select this option then I get another screen that allows me to select Trezor. At that point (no Trezor connected) I get an error message that Trezor wasn't connected. So you can duplicate this problem without actually having a Trezor to test.
It's quite strange, I just tried this with git tag "2.0b2".
I had to copy folder "trezorlib" from python-trezor to electrum folder to get anything trezor related to work at all.
But even then the trezor plugin was still greyed out in plugin list.
However: I was able to create a new trezor-based wallet (wtf?)
After having created the wallet, the plugin was not grayed out any more and enabled.
maybe we should take this to
https://github.com/spesmilo/electrum/issues