Try first the 32bit version. In the past it only worked with that version.
Someone said that it now worked in 64bit but that did not work for me.
Make sure you have this file in the David folder:
EDSDK.dll (version 184.108.40.206)
Connect the Canon by USB to the computer. Start the camera
Select the Canon 60D in the camera setup section of David ("choose video source").
It should be there.
It should work.
Panasonic GH4 4K with lens 12-35, Inogeni 4K to USB3 hdmi capture device, projectors: Acer K135/Acer K11/NEC V260X, Canon 60D, macro 60 mm, MagicLantern