I run three monitors. When Flyinside FSX is started, it opens up on my far left monitor, otherwise known in DirectX as \\DISPLAY3. However, when I try to open up any of the game's panels, like GPS, those want to open on \\DISPLAY2. This results in a very disturbing flashing in the VR goggle (Oculus Rift), and the FSX program hangs. I have to force quit it every time. It also crashes when I try to move the FSX window to the desired display after everything loads up.
I found the INI file in AppData, and it shows me the display number its using, which happens to be \\DISPLAY3 as expected. I can't edit the file to change it. It always reverts back to the original display settings. Once when starting Flyinside FSX, I was able to quickly grab and move the FSX window before the FSX welcome screen appeared and move it to \\DISPLAY2. When it was there, I was able to open panels and they would appear in the cockpit in VR. But I've never been able to repeat that technique without it crashing every time I do so. So I know it's a window placement issue. Being able to modify the starting window for the game will save a lot of trouble.