Hi
I don't own any Behringer hardware but I tried to check
the Neutron panel and I can't see any CV Clock input so you'll have to sync it (basically, the LFO) through MIDI. That's quite ok, since there's actually no Clock CV out from BeatStep
That will also send MIDI Notes, so that takes care of BeatStep->Neutron control and sync
The 182 module has a few GATE/Trigger inputs so you may connect on of the Envelope's GATE in to the BeatStep CV out and the other to Neutron GATE out.
This is just a suggestion, since, as I said, I don't own any of those, so anyone owning them might have a different approach
Hope this helps.