Here is my reasoning, please comment on anything you feel is wrong or anything I have ommitted:
However you look at it, this
eGalax I USB Touc
should be this
"eGalax Inc. USB TouchController"
the string is mangled, which to me implies a communication problem.
(OK it could possibly be 'eGalax Inc. USB TouchScreen' or even just 'eGalax Inc. USB Touch' on a different model release, but no way are they going to truncate the 'Inc' part of the company name).
Software communication issues:
It is unlikely to be a kernel module (udlfb) problem, but it has not been ruled out, you would be the only reported user suffering it if it is.
The module in some form has been around since 2009 (tried & tested in the wild).
The rest of the USB infrastructure is well established, and would most probably affect other USB devices if it had issues.
Hardware communication issues:
There is little point in swapping USB ports on the plug, they are all on the same hub.
On a PC you will (usually) be able to swap between USB 1 & USB 2 ports (worth trying).
If you get the same when plugged into a different computer running a different OS, the only component that has remained constant is the monitor itself.
You may not need to install widows drivers (if it's been around since 2009, is should be in Windows 7).
If you can get at 'device manager', look for the touchscreen identification string.