I am connecting my U2415 to a MacBook Pro using USB to data cable. There is some connection but it continually goes blank and nothing is working? Does this connection work?
As you can see in the image below taken directly from the U2415 page, the Apple proprietary hardware, operating system, and drivers were not tested/validated by Dell.
We at Dell are not trained in the usage of the Apple OS. You should ask the Apple users on their Forum for troubleshooting opinions.
I can tell you that the U2414H does not support the usage of USB-DisplayLink scenario. Ask the Apple users about USB dock options.