Search the label GET_SUFFIX in the REXX procedure TAUCMSSV and adapt the named library types in the exit to link them to the correct file suffixes. The Editor used to open a staging version component depends on the file suffix. For example, in TAUCMSSV the ChangeMan library type SRC is linked to the file suffix COB by default. Without customization, all staging version components located in type SRC would be opened with the COBOL Editor.
In addition, adapt the list of dependent library types to your needs. Defaults are LOD and LST.