Is it possible to edit the transaction code through the Editor in Studio 11?
Studio 11.0 - 11.3
The Editor in version 10 that was required to make these changes was removed by design. It was found that if a user made an accidental change the script could become corrupted.
One workaround is to save the Studio 11 file as v10 compatible and then open in 10.x make the changes in Editor and then reopen the script in Studio 11. How to Change the transaction code used in a Read from SAP script
Starting with Studio v11.4.0 it is now possible to change the Recording Time (core recording time) and Transaction code script properties in the Properties panel.