Instant Actions: merge fields with drop-down options

Instant Actions: merge fields with drop-down options

Hi there, 

I would like to set up a workflow where a new Deal is created when the status is live and the closing date is coming up to a year. This would be a renewal opportunity for the deal. 

I've set up instant action: Create Record Type = Opportunity and I would like to pull in as much information as possible from the original deal. 
I can merge fields by typing # in look-up fields, but when the field is a dropdown - an option has to be selection I can't seem to make it depend on the original deal. 
As some of these fields are mandatory on creation, it's blocking me from saving the workflow rule. 
Is there a way around this or do I need to set up a personalised function? 

Thanks