Add new Field in Manager Layout

Hi,

I need to add a new field in the customized manager layout of copied READY_TO_SHIP_OB_LINE. It could be a pseudo field or enabling a tag.
I tried to enable the tag and entering a value in that. But the value is not getting saved in database. Does anyone have the idea about the code of pseudo field which should be referred in this case? We are using 6.2.0 version of OTM.

Thanks in advance.