FWIW, I just installed the lastest build (Beta 2 - 41385) and get similar results as with Beta 1.
The difference this time was that while the entirety of the user interface hung, background processes continued to function. This allowed me to SSH in from another machine and execute 'sudo shutdown -r now' to recover.
Thinking that perhaps a concurrent installation (not execution) of Parallels was perhaps the problem, I uninstalled that and then re-attempted the operation. Unfortunately, the same results.
Sorry to hear that this device still isn't working.
I haven't seen anything like this in my testing. There's some chance we might be able to get a PicoScope for testing purposes, but you can help us diagnose the problem by collecting some log files.
Make sure your VM is powered off or suspended, then open up your VM's .vmx file with a text editor like BBedit (TextEdit can corrupt the line endings) and add the following lines:
usb.analyzer.enable = "TRUE"
usb.logging = "ioctl"
Now repeat your test. The interesting logs should be in "vmware.log" in your VM's directory. Send me that file- it will probably be pretty big. You can try attaching it via the forum. If that doesn't work, put it on the web somewhere or email it to firstname.lastname@example.org. You can compress it if you like.