I am not a ableton user nor do i use your interface but if you connect the adat out to the interface you should see the inputs in ableton where ever you select the current inputs. in my set up the MPC 5000's output 1 & 2 show up as 10 and 11 in Logic.
From Page 195 of the manual...
http://www.mpc-forums.com/files/MPC5000/mpc5000_reference_manual_v2.00.pdfNormally, the ADAT output follows the chart below:
ADAT Channel Output
1 STEREO OUT L
2 STEREO OUT R
3 MIX OUT 3
4 MIX OUT 4
5 MIX OUT 5
6 MIX OUT 6
7 MIX OUT 7
8 MIX OUT 8
However, by setting the value of parameter 'ADAT Chan 1+2' to ASSIGN OUT 1&2, this will allow all eight of the
assignable mix outs to be sent through the [ADAT OUT] port.