Now taking the Trezor back to the 64-bit machine it appears to be doing the correct things with the standard wallet behaviour (no firmware issues now) but is still really slow and sluggish to keyboard and mouse inputs.
If this problem persists, it may be caused by some issues in plugin. In few days we'll releae Trezor Bridge for public testing (replacement for Trezor Plugin), which solves many of known issues across all browsers.
Another point on the plug-ins are they open source?
Trezor Plugin is closed, but new Trezor Bridge is opensourced:
https://github.com/trezor/trezordIt's not released to public yet, but if you want give it a try... :-)