Since you are going to be putting pizz. and arco on the music anyway, you can get get the instrument change to show that instead of adding extra text objects. After you have the instrument and correct patch number selected, you can change the name of the instrument as well as override placement (prob. want to uncheck "preserve width") and visibility to show it.
!NoteWorthyComposerClip(2.5,Single)
|PerformanceStyle|Style:Legato|Pos:0|Visibility:Never
|Clef|Type:Treble
|Instrument|Name:"Violin"|Patch:40|Trans:0|DynVel:10,30,45,60,75,92,108,127|Pos:10
|Note|Dur:4th|Pos:-5
|Note|Dur:4th|Pos:-4
|Note|Dur:4th|Pos:-3
|Note|Dur:4th|Pos:-2
|Bar
|Instrument|Name:"pizz."|Patch:45|Trans:0|DynVel:10,30,45,60,75,92,108,127|Pos:8|Visibility:Always
|Note|Dur:4th|Pos:-5
|Note|Dur:4th|Pos:-4
|Note|Dur:4th|Pos:-3
|Note|Dur:4th|Pos:-2
|Bar
|Instrument|Name:"arco"|Patch:40|Trans:0|DynVel:10,30,45,60,75,92,108,127|Pos:8|Visibility:Always
|Note|Dur:4th|Pos:-5
|Note|Dur:4th|Pos:-4
|Note|Dur:4th|Pos:-3
|Note|Dur:4th|Pos:-2
!NoteWorthyComposerClip-End
HTH