Another Track Scale Thread

So I’m sending program changes from OT Midi out into AR Midi in and then AR Midi out to DN Midi in. OT Master Lenght is set to 128. AR is set to LEN Inf and CHNG 128. When I’m chaining a Pattern on the OT it changes in sync with the AR. Whichever setting I try on the DN though it takes an even number of bars to change to the next pattern. In my previous setup where there was a DT at the place of the AR I had somehow set the things right but I still can’t get my head around the CH.LEN, M.LEN, LEN, CHNG and all the other track scale settings. Can someone please try ELI5 to me or at least tell me how I should set it up so that it all changes in sync? Thanks

midi thru instead of midi out of course. pls ignore