BQ20z65 what subclass is Max Capacity Err in?

I'm using an ENCR file for the BQ20z65 that allows me to access three hidden registers in the Gas Gauging page of dataflash: OCV Wait Time, DOD Capacity Err and Max Capacity Err. I need to write those values programmatically using the WriteSMBBlock function from the BQ80xRW.OCX file. I can access OCV Wait Time (subclass 0x50, offset 11, length 2) and DOD Capacity Error (offset 17, length 1) but when I read subclass 50 I only get 32 bytes of data, so if Max Capacity Err is located in that subclass I'm not reading it. Two questions: 1) What subclass is Max Capacity Err located in? 2) How do I read/write it? Thanks to anyone that can help me quickly.