Hi Ali,
I'm not sure that you answered my question. It's probably my fault. Let me try again.
1) My goal was to start a new "Custom Set" in the Registry referencing the instructions on the website ( reference "For collectors who assemble sets in their own unique ways, custom sets are ideal. Custom sets let you define the theme and choose which coins are eligible. NGC and PCGS-certified coins as well as raw coins are eligible for NGC Registry custom sets." and "....some collectors choose to assemble sets in unique ways, as personal expressions of what they find fascinating about collecting. Custom Sets allow collectors to post sets of any type."
2) With that goal in mind, I created (on February 15, 2020) a Custom Set entitled "Rarity versus Scarcity? What is the difference, if any? Fine Examples of Rare and Scarce Coins" and wrote my collecting goals for this custom set.
3) I just found this set created on February 15, 2020, but am now unaware as to how to add NGC coins (already scanned and added to my competitive coins) and PCGS coins (awaiting approval) and Transfer images of these coins to this newly created custom set.
4) Can you advise me how to go about this?
Thank You