I just bought a Lenovo Flex 3 with Windows 10. I wanted to use the UD-5900 to do all the obvious things: connect two remote monitors and other peripherals so that I can come and go with ease.
I installed the software through the website link as recommended in the instructions (and not from the enclosed CD) and rebooted. Everything appears to be working, like the lights and ethernet connection, etc., but the two monitors are blackscreened constantly. Both are 23-24 inches, one is a Samsung and the other is an Acer. Both have DVI outputs with one using the HDMI and the other using a DVI input into the UD-5900.