Install the same Mantis version on Windows (which mantis version is that?) and copy the database from synology to windows.
Once that works, follow normal proces to upgrade the the latest version of mantis.
Although I understand the request, I do not think this can be solved by a plugin, this would really require an overhaul on the way custom-fields are defined and presented. If this were to be changed then also one should have the ability to have different groups of custom-fields, the ability to prese...
This is handled within core/columns_api.php. Check out the function function print_column_status. Here you can suppress printing of the text (and/or the user in charge). This would require to make this change every time after updating Mantis. It also expects everybody to exactly know what each color...