I tried looking at this yesterday but, unfortunately, it only seems to work with a particular implementation of LiquidCrystal_I2C, the same one as compatible in the New LiquidCrystal Library.
My I2C backpacks work with the other I2C implementation, the one that controls the backlight through the I2C bus, rather than a dedicated arduino pin.
Are thee any plans to make MENWIZ compatible with more than one LCD connection method, as it rather limits scope for take up in this guise, but otherwise looks like it could be an excellent library.
If it were to be included as core library then it would need to work with any LCD connection, certainly with the shields available.
Many thanks.