Hi,
You will not be able to enter the data to SAP GUI frontend editor control using BDC or so called batch input: see note 311440 - Batch input and controls.The reason is simple - there is no frontend available during batch input... There is no easy solution to this, I believe. One would need to know the capabilities of the API you are using to interact with SAP to even suggest different method. If the BDC is the only method the API supports, something needs to change in SAP backend system - in Z_RELATIONAL_VIEWER. That would still be a messy solution - the Z program could try detecting if it's running under batch input and expose input fields for two text lines instead of editor control...
This is one of the main reasons the Business logic (Maintaining Activity log in your case) must always be separated from UI - so other solutions (like your macro) can access it without having to go to UI or having to deal with the limitations of things like BDC...
cheers
Jānis
