Hallo Jamie,
thanks for your programs. I am using your works for EU3, and it is very useful for all modders. I am glad to hear that you are willing to make a Sengoku program.
However, I am bit worried about your suggestion. If you don't own the game but only the Demo, you and we testers can't truly share workable and unworkable things of the program. In addition, we contact per PMs, it means testers can't discuss with each other about your program in the mod subforum.
Despite of these disadvantages, I would join to this project. If you wish, I will make a thread for your program.