Look at a model definition. You give it an absolute start channel or you give it a relative channel number based on an output number that you define in setup. As I understand it the output number is basically the line number in setup. I have all my models in a spreadsheet and it keeps track of all the channel numbers so that works good for me and I don't need the from output. Some people like to keep track of a device like a Sandevices unit that is defined in setup and has an output number with each connections starting at 1. You can take your choice. Gil likes from output, others, like me, like to use absolute channel number. Either way works, but YOU have to decide.