I think i'd advise doing some research into the fundamentals of how triggers and gates work in analogue drum machines and modular synths.
As that MK107 only has a single output, you would only be able to use it to drive one CB55 sound at a time, so you'd need 5 of them running alongside each other to trigger all four CB55 sounds and the accent. Its not an uncommon DIY approach.
You need a 5v trigger pulse to trigger the CB55 sounds properly so you'd have to turn up the pots to maximum for a trigger step, and down to zero for a non triggered step, although personally i'd just replace the pots with on/off step switches for a drum sequencer.
The problem you are probably going to have is that unless you can shorten the length of the pulse on each step, you'll just see a variable voltage at the output with no gaps. This probably isn't going to trigger the CB55.
Normal trigger pulses might be 10ms or more long, but however log they are, there will be a 0v gap before the next pulse or the sound won't retrigger. The CB55 triggers on the rising edge of the pulse, but if theres no gaps between pulses, there won't be any rising edges.
To drive the CB55 with midi you'll need a midi to trigger converter. You can buy these at various places around the net. Alternatively you could just get some kind of machine with trigger outputs built in.