Some plugins remove the TBM's crash handler, which prevents us from getting good crash logs and diagnostics to be able to debug problems. Please remove all plugins except for Gizmo and retest if you can get it to crash again. Since you said it happens during preflight, it should be a simple matter of a few minutes to get it to crash. If the crash doesn't occur anymore, try putting some plugins back and tracing down which one is causing it. Any info you can provide us on plugin incompatibility is valuable, as we can then try and address that incompatibility.