This is most likely coming from the specific file it mentions in the error, Dist Send Result File To RT.vi. The error 6 means the file can't be found. One thing to try first is to add this VI as a Dynamic VI in Application Builder. Another option is to change the path that this VI is invoked from, or is not called by an Invoke Node at all.
I hope this helps, feel free to contact support if the problem continues.
Regards,
Robert Jackson
Application Engineer