In updated system MS Word used as default Smart Forms and SAP Script text editor. In cloud system it is mandatory.
You can configure text editor with two ways. You can run ABAP report RSCPSETEDITOR in t-code SE38 for changing it. Other option using t-code I18N. In this t-code you need to open I18N Menu -> I18N Customizing -> I18N System Parameter. Select smartforms_editor as Parameter and emtpy as Value.
If you haven’t got enough privileges to change configuration, you can manipulate it in debug mode. These configuration saved DB table TCP0I as smartforms_editor and sapscript_editor. You can add break point in NLS_WORD_ENABLE function in t-code SE37. This function called by Smart Forms in first use of editor.
In S/4HANA system you need to add additional break point for running old editor. Add break point to CL_GUI_RTF_EDITOR and CL_GUI_SAPSCRIPT_EDITOR classes constructor below line and bypass the raise exception line.
* is not supported in S4H
if cl_cos_utilities=>is_s4h( ).