Can you check the options for this feature?
http://prntscr.com/uhpszgaccording to the idea for binding, you need to find a client and a business process
"Search for a client by field:" - what is the field? in a business process? where does customer data come from? from payment?
from what part?
"Search external process ID by pattern (eg #ordercode1c):" - what is pattern? where does the data come from? and what are you looking for?
i.e. if you sort out the external ID from all business processes and look for it in the incoming payment?
or is it a template to select an ID from the process and then iterate over all processes ....
from what part to allocate ID?