Enhance SAPGUI Transaction by Side Panel??

Hi experts,

I need to enhance a classic GUI transaction which no any screen(dynpro) enhancement point available.

The requirement is to add customer attributes in a table format.

I am able to put this GUI transaction and a customer CHIP together, and move data from SAPGUI screen to CHIP by TAG.

My thought is when user clicks the save button on the GUI transaction, data inputted in the CHIP page also updated into table automatically.

My question is: how to move data from CHIP back to GUI application when save triggered in GUI application?

Thanks!