use it as the clock - send it out on say channel 3 of your interface and set the tempo in reaper
if you are going to make several passes it can help keep everything in time - especially if you want to change tempo during a track - set the tempo changes in the daw you can also use it to start/stop etc - hopefully when you record then every track you record from the modular will start at the same place which makes life a lot easier
if you are going to want to add soft synths or any processing that is time based in the box
if you are adding to something already recorded
etc etc
"some of the best base-level info to remember can be found in Jim's sigfile" @Lugia
Utility modules are the dull polish that makes the shiny modules actually shine!!!
sound sources < sound modifiers < modulation sources < utilities