Hi Chris,
In SPRO use the following path:
EHS > DG Management > Interfaces: Filling and Distribution > Filling > Specify Assignment Objects for Filling.
The four fields you noted above are all in the DGTM2 table, Reference the class and characteristic in the config activity.
You should also fill out the config activity: EHS> DG Management > Interfaces: Filling and Distribution > Common Settings > Specify Checkbox Structure for Dangerous Goods Master. This will let you to define if you want to overwrite data on re-filling.
There is a custom ABAP BAdI you can use if all else fails.
Hope this helps.
Eric Perala