You can open the MIDItester patch in the extras menu.
On the left you will see the incoming MIDI data, after selecting the right input device for the midi port.
I don’t know the UC-33e, but it will probably be cc messages
for the faders and knobs, and noteon/off messages for the buttons.
You can use the objects [ctlin] and [notein] to get those.
Also have a look at [route], which will make routing easier.
(I wonder what japanese bablefish will make out of this ;)