Driver Ati Radeon Hd 4200 Windows 10 here. With the generic driver actually I didn't had any 'touch point', because my touch was recognized like a touchpad (moving the mouse cursor) but in a reverse manner (when I touch from bottom to top, the cursor moves down, when touch left to right it was going to left). Also, touching the screen and moving the finger it was like moving a mouse with the left button pressed. To be honest, completely unusable.
With the pen it works as usual (because it's another sensor). Installing the same driver as I was using in Windows 8.1 has restored the touch capability and I have two touch points (as I can zoom in and out using a pinch movement). I've forgot to mention that you don't need to run the setup. Go to Device Manager, find the USB Controller (next to your mouse) and click to update driver. Select to choose from a device list, then select that you have a disk and point it to the folder you've extracted. It should find a device named 'EETI PCAP MultiTouch Digitizer' and it may ask if you really want to install this driver, and you should confirm. These were the steps I remember doing, but I can give more details later when I get home.