Apologies for the late reply… it appears that my notifications for the forums have reset so I didn’t get any notification that you posted on here!
I have about 80% of the blueprint complete… but I have been working on a game that has been chewing up all my time… However, I am -hoping- to pull myself away and invest time in finishing this soon. As for the cost… I’m thinking low to be honest 
Something in the area of USD $10, but it will depend on how much work the documentation ends up being as well to be honest.
Thanks for the kind words