The changes made in version 5.1.0 are mostly about "Login Agent" supporting keyboard-interactive method, and adding SOCKS 4/5 support for SSH port forwarding. So it's somewhat odd that you're experiencing a display related issue with version 5.1.0.

If Token2Shell/Mobile did not display *any* message and the cursor was just blinking at the upper left corner, it's probably caused by your device having low memory or resource.

Windows Mobile devices featuring VGA or higher resolution such as your Touch HD can easily run out of memory space when you are using graphic intense applications such as Web browser or media player. Some of those applications may still be running in the background even if you close the application.

So if you are seeing any odd behavior in Token2Shell/Mobile or any application, check available memory and make sure you have at least 1MB+ free space before running the application.

Also, if you are using a "custom" ROM that was not issued by the manufacturer, please be aware that such ROM may have problem managing the memory. Since such problem is not so apparent and happens randomly, we strongly recommend only using the ROM image that was officially released by the manufacturer.