wyse usb imaging tool 2.1.2 not detecting usb drive on the drop down but visible on drive value is 1

exception error in  the given key was not present in the dictionary

at system.thowhelper.throwkeynotfoundexception() function

model wyse Thin client z family 7010 WES Z90DE7 32 bit

.net framework installed 4.6.1

per usb imaging tool required is net 3.5

is this latest model compatible with functions calls made from 4.6.1 to 3.5 framework?

Any idea why the sandisk 32 gig usb flash drive is not dectected by apps though it is detected by the operating system mounted as D drive?