I use the "SetCursor" command to put the cursor into a particular table cell. This works well. In addition, I would like to position the cursor at a certain offset in the field so that the user can immediately write at this position. I use setcursor cell[All items,Material,2] offset="5" but this has no effect. What could be the reason?
This depends on which setting you have chosen in the SAP GUI options:

Interaction Design

-> Keyboard Settings

-> Automatically select complete value when entering a field in insert mode (INS)

If the option is "on" the cursor setting within the field ("offset="option in SetCursor) is ignored. With "off" the SetCursor works correctly.

This is SAP GUI behavior which GuiXT cannot change.