I just purchased these 2 engines and when I installed them, they made all my JR stuff (just about) faulty. After some researching I discovered the red and green coronas that came with one of the new engines (or both) were faulty. To fix it I installed another JR engine and it opened the corona files for edit since it was already installed. I then submitted the open edits and all was fixed again. Just thought you might like to know about this.