Primal on iOS doesn't allow you to add a NWC node, but it would be nice if you're region locked to not have the wallet icon show up? The Android version allows you to zap from the built-in in wallet or your own with NWC. Damus is a great app though. You should love it. Did you enable Zaps with the external script?
https://nostrscript.suhailsaqan.com/
My screenshot is from an Alpha version of Damus for Android.
No, I simply connected Damus to Nostr wallet connect on my node.
All zaps are now automated & come straight out of my LND without any external payment screens etc.
As for receiving Zaps, I simply just added my Zeus Pay lightning address to my profile
Great! That's what I do too, on Amethyst. I run an LND node with nostr:npub1u8lnhlw5usp3t9vmpz60ejpyt649z33hu82wc2hpv6m5xdqmuxhs46turz's NWC app. It works great for Zapping.
That website I linked allows you to send zaps on individual notes, not just profiles. It's just a simple toggle button. Check it out.
Done. 
I'm currently adding Nostrudel (my self hosted desktop client) to NWC too, so I may test out the connection for zaps with you Derek. 🤣
