We find it easier , faster, more secure and simpler to work with the current engine rather than Repny. People here are accustomed to Renpy and we get that but since we are a team of multiple people working, the current engine allows us to multi-thread parts of the game.If it's not a secret, why?
Once we have a couple of versions out , and we find someone trustworthy willing to port it to Renpy we will gladly give them the assets to do it while we monitor that it is done properly.