I do not understand your question. If you want a dotted half note as the value of the beat, you could use a time signature such as 6/4 for example:
!NoteWorthyComposerClip(2.0,Single)
|Clef|Type:Treble
|Key|Signature:F#
|TimeSig|Signature:6/4
|Tempo|Base:Half Dotted|Tempo:55|Pos:7
|Note|Dur:Half,Dotted|Pos:0
|Note|Dur:Half,Dotted|Pos:1
|Bar
|Note|Dur:4th,Slur|Pos:1
|Note|Dur:4th,Slur|Pos:0
|Note|Dur:4th,Slur|Pos:-1
|Note|Dur:4th,Slur|Pos:-2
|Note|Dur:4th,Slur|Pos:-3
|Note|Dur:4th,Slur|Pos:-2
|Bar
|Note|Dur:Whole,Dotted,Accent|Pos:-2
!NoteWorthyComposerClip-End