I was trying to work my way through Airline2Sim's Q400 training course, replicating it as closely as possible, so I set up the Q400 at EGNX and saved the flight.  On a later date, I reloaded that save, then realized they were flying in a particular set of weather conditions, so used custom weather to replicate it as closely as possible (mainly winds at 282/8).  Overwrote the save (unfortunately), then tried to tune ATIS.  Within a few seconds, I got a CTD.  Reloaded FSX and the save...another CTD within maybe five seconds (while it still had the "default failures loaded" banner up, and I hadn't touched a single control).  Tried it again with the same result.  I then reloaded the save and immediately selected weather, and set it to the default "clear skies" setting.  Returned to the sim, and no CTD.  Don't know if it was the specific set of weather conditions/aircraft/airport, but I was getting a consistent CTD until I changed them to a "default" set.

 

It appears you investigated the CTD and found the solution by changing the weather to the default clear skies setting.  Real world weather is real world weather and I do not see how it could be saved, and later open up the saved flight.  That probably is the cause as the saved flight, when reloaded, cannot find that real weather. Only the default weather scenarios are the same.  Just a guess on my part. 

Best regards,

Jim

From your post it doesn't sound like you're looking at the Dash 8 as part of the problem, but even so I thought I'd pass along that we tested the Dash with all types of weather engines and weather (custom, historical, real world) for almost 6 years without any issues.

 

 

So, if I understand this correctly, it would appear that you have to choose the weather (a default setting or the WX engine of your choice) when first setting up the flight, but you can't save it, then reload and change the weather afterwards.  Correct?

P.S.: Just to clarify the "real world weather is real world weather" comment.  I didn't use a weather engine, I edited the weather myself from within FSX's "custom" setting.