In the Behringer website, there used to be custom Behringer drivers for this particular device. Now the site just redirects to ASIO web, where you can download the standard ASIO drivers. As they're not custom, they don't work as good as the old drivers (keep reading).
Differences with new drivers
There is one major very important difference.
With the new drivers the system install a generic USB audio driver and the PC sees the interface in Recording devices as a microphone input. When you try to record with a simple software like Audacity or simply you want the audio to sound through the Stereo Mix, you can only hear what is plug in the mic input of the interface. To use the second channel you have to use complex software like DAWs and mess with ASIO.
With the old drivers the system install a custom Behringer USB audio driver and the PC sees the interface in Recording devices as a line input. Now, all the inputs of the interface work without further trouble. You can capture the sound with the program you want and it will sound through the Stereo Mix as well. You don't need ASIO for anything.
It has been a hard job to find the old drivers in the internet for this model but here they are:
Behringer UM2 64-bits Windows 7/8 drivers, version 2.8.40.
(Sorry but I don't have any other version, OS, nor architecture).
Behringer UM2 64-bits Windows 7/8 drivers, version 2.8.40.
(Sorry but I don't have any other version, OS, nor architecture).
Update (23/06/2020): Reader Ceiba Groove comments that got the drivers working in Windows 10 under compatibility mode.
https://mega.nz/#!fpF2RD6S!tdk6sCz1ePU77DMySDpJIsauvOCW-Zjxve_ixqq71UI
The 'Readme' file says they should work for
'UMA25S, UCA200*, UCA202, UCA222, UFO202, UCG102, iAXE393/624/629 and many more.
*bundled with UMX series, XENYX mixers, PODCASTUDIO USB
This driver does NOT support the following BEHRINGER hardware:
C-1U, BCD2000, BCD3000.
These models have separate dedicated drivers'
https://mega.nz/#!fpF2RD6S!tdk6sCz1ePU77DMySDpJIsauvOCW-Zjxve_ixqq71UI
The 'Readme' file says they should work for
'UMA25S, UCA200*, UCA202, UCA222, UFO202, UCG102, iAXE393/624/629 and many more.
*bundled with UMX series, XENYX mixers, PODCASTUDIO USB
This driver does NOT support the following BEHRINGER hardware:
C-1U, BCD2000, BCD3000.
These models have separate dedicated drivers'
Enjoy, and if you need some help, let me know in the comments.