You have the exe package that contains everything to update your InsydeH2O EFI under Windows enviroment. What you must to do?

1. Extract the exe package with 7-Zip.
2. Find the file platform.ini.
3. Open that file with a text editor.
4. Search for the section [BackupROM].
5. Set the atribute Flag to 1.
6. Set the atributes FilePath and FileName to empty value.
7. Save changes.
8. Proceed to update yor BIOS safely!

To be clear, your platform.ini file must be set like this:

[BackupROM]
Flag=1
FilePath=
FileName=

This configuration establish to make a backup for the current BIOS and new BIOS, and save them to same directory where your platform.ini file is located.