Hi Paul,
Based on the log it seems to me that you actually run VCD 1.5 (not 5.1). Could you tell me Version/Build date from Help > About? If that's the case and you can't find a way to execute your script synchronously or the timeout of 100 sec is not enough, I would recommend to run your stuff by scheduling a separate Windows Task to run after reboot (this is how we do it in VCD 5.1.x):
\\system32\\schtasks.exe /create /sc ONSTART /rl HIGHEST /np /z /v1 /ru SYSTEM /tr "command" /tn "My Task"
Just remember that you might need to delete it afterwards, since Windows often fails to do so, even though the arguments instruct to do it.
/Andrii