It seems Metaquotes fixed error causing the permanent Error 131 message during testing in disconnected mode. The fix has been implemented in build 891, which is not delivered as an official release. Therefore, here is a quick update for those who do not want to wait for the official release.

Download terminal-891 (you might need to override security warning). After unwrapping the zip, replace the terminal.exe by the new one from the 891 zipped download. No further action is needed.