Hello Japie, Blindboy and Anarchia,
First you’ll need to go to Arturia website and install the MIDI driver that works with your specific operating system.
http://www.arturia.com/evolution/en/products/MiniLab/resources.html
Once that is completed, you can open Cubase and go to Devices>Device Setup>MIDI>MIDI Port Setup. There you should be able to see that Cubase is seeing your Arturia MIDI driver. From there you can create a Instrument Track or MIDI Track and the you can access the available Arturia MIDI Ports from the Input and Output Tabs in the Track Inspector.
*Be advised that unfortunately Cubase LE5 is discontinued and no longer supported, thus it may not be compatible with newer VST’s that support VST3. Cubase LE5 does not support VST3. I would advise contacting Arturia and see if they also support VST2 and 2.4 and if they have tested this product on Cubase LE5.
Regarding the UR44 which uses Cubase AI7, it supports VST’s but you’ll need to install the MIDI driver as mentioned above.