To see "Funnel Steps" within a parent "Funnel" you need to Double Click that funnel.
To see "Products" within a parent "funnel Step" you need to Double Click that funnel step.
When you enter a specific Funnel or Step, You will be able to:
1. See options specific to that funnel or step only.
2. You'll be able to sort your steps or products (you can drag and drop them all around).
3. You'll be able to see that option "Set As Order Bump" too.
I think some couldn't figure out that, because it's not mentioned anywhere on the app to double click except on the documents/tutorials... So we might remove that option, and improve it a bit on the upcoming update.
Hope that helps!