Flying Fries Hughes XF-11----Loved it before the Update.

I have flown the XF-11 in MSFS 2020 for months.  The sound of its huge engines is great if you're a prop guy like me.  Had absolutely no problems with the aircraft until the latest update to v. 2.1.  They apparently have now made it into a study plane.  I have been unable to finish a flight in the last five times with it.  The engines just stop mid-flight.  I've gone on-line and watched videos about fuel management and engine management to no avail.  Babied the engines--flown at different altitudes and speeds, watched EGT and have not pushed it to the max.  Does anyone else have this problem? If so, if you've solved it, please share your solution with me as I really like this plane.  Thanks