Hi Ian,
I am not from Laminar Research; just a flight simmer from down under.
I notice you have downloaded the latest beta version of X-Plane. To the best of my knowledge found in the following link the beta version is still active and the official release has not been made as yet. Have a look at the following link found at https://www.x-plane.com/kb/x-plane-11-40-release-notes/ Unless Laminar released the official version late Friday then my other sources don't reflect that change.
Unless you are an experienced user of X-Plane you should always stay away from that version and let others find the faults/problems.
I have just opened a newsletter email from X-Plane.Org, no relation or connection with Laminar (X-Plane.Com), advising that X-Plane 11.40 is still in Beta format and any 3rd party aircraft will not currently work and flight simmers should remain with XP11.36 for the time.
Although your aircraft is a LR version the beta version restrictions may stlll apply.
Austin Meyer, the X-Plane creator, is controlling the Beta version and you should make direct contact with him if the problem continues. Details of the beta update along with Austin's contact details can be found at https://www.youtube.com/watch?v=v4UfGE-JJY4 and at https://www.youtube.com/watch?v=WROEk_Jv33w
To attach your log.txt file you need to follow the information provided by Greengolfer15 in the following link found at https://questions.x-plane.com/?qa=blob&qa_blobid=17830136656522860642
As a side issue 21 Sept was a good day for me.
Hope you get a solution.
Glenn