How do I trigger different samples loops from an external midi controller

Hello there, I have an Octatrack MK1 on the way and I basically have two ways I want to use the machine.

The way I want to use it for live seems fairly simple, but I am having trouble working on my workflow for my studio plans.

I do all of my songwriting on a Squarp Pyramid, and I want to continue to use that as my main sequencer, but where the Octatrack comes in is I want to be able to record guitar loops/MPE synth audio into the Octatrack (up to about 16 bars probably), and then trigger those loops from my Pyramid, and I can’t figure out what would be the best way to do this just from my time with the manual.

Also, is there a way to trigger sample recording so that it starts at the start of a bar after clicking a button?

Thank you so much, I think this will be a great utility device for me!!