I was looking into doing this with a user object (PageTxtMaestro and PageTxt) provided by NWC, but while I can manage one above the top staff, there is not enough offset range for the "Y" positioning parameter to get to the middle of the page, at least in my experiments.
However, there is no reason you couldn't use a simple series of text <X> directives to do the same thing.
What you would need to do, regardless of using a PageTxt object, OR simple text is use the Boundary object <]> to set and reset the top space on the required systems/staves.
There are also objects by RickG called Markup and MarkupPage that would probably work but I'm not familiar with their usage.
See example below which uses a PageTxtMaestro object for the first lot of text and successive text objects for the second:
!NoteWorthyComposer(2.751)
|Editor|ActiveStaff:1|CaretIndex:1|CaretPos:0
|SongInfo|Title:"Piano Template"|Author:"<Name>"|Lyricist:""|Copyright1:"Copyright © <Year> by <Name>"|Copyright2:"All Rights Reserved"
|PgSetup|StaffSize:18|Zoom:5|TitlePage:Y|JustifyVertically:Y|PrintSystemSepMark:N|ExtendLastSystem:N|DurationPadding:Y|PageNumbers:0|StaffLabels:None|BarNumbers:Plain|StartingBar:1|AllowLayering:N
|Font|Style:StaffItalic|Typeface:"Times New Roman"|Size:11|Bold:Y|Italic:Y|CharSet:0
|Font|Style:StaffBold|Typeface:"Times New Roman"|Size:9|Bold:Y|Italic:N|CharSet:0
|Font|Style:StaffLyric|Typeface:"Times New Roman"|Size:8|Bold:N|Italic:N|CharSet:0
|Font|Style:PageTitleText|Typeface:"Times New Roman"|Size:24|Bold:Y|Italic:N|CharSet:0
|Font|Style:PageText|Typeface:"Times New Roman"|Size:12|Bold:N|Italic:N|CharSet:0
|Font|Style:PageSmallText|Typeface:"Times New Roman"|Size:8|Bold:N|Italic:N|CharSet:0
|Font|Style:User1|Typeface:"Times New Roman"|Size:13|Bold:N|Italic:N|CharSet:0
|Font|Style:User2|Typeface:"Times New Roman"|Size:13|Bold:N|Italic:N|CharSet:0
|Font|Style:User3|Typeface:"Times New Roman"|Size:13|Bold:N|Italic:N|CharSet:0
|Font|Style:User4|Typeface:"Times New Roman"|Size:13|Bold:N|Italic:N|CharSet:0
|Font|Style:User5|Typeface:"Times New Roman"|Size:8|Bold:N|Italic:N|CharSet:0
|Font|Style:User6|Typeface:"Times New Roman"|Size:8|Bold:N|Italic:N|CharSet:0
|PgMargins|Left:2.54|Top:2.54|Right:2.54|Bottom:2.54|Mirror:N
|AddStaff|Name:"Right Hand"|Label:"Piano"|Group:"Standard"
|StaffProperties|EndingBar:Section Close|Visible:Y|BoundaryTop:18|BoundaryBottom:10|Lines:5|WithNextStaff:Brace,ConnectBars|Color:Default
|StaffProperties|Muted:N|Volume:127|StereoPan:64|Device:0|Channel:1
|StaffInstrument|Patch:0|Trans:0|DynVel:10,30,45,60,75,92,108,127
|Boundary|Style:NewSize|Upper:24|Lower:6
|User|PageTxtMaestro.nw|Pos:0|Class:StaffSig
|User|PageTxt.nw|Pos:0|PgStyle:Title|Text:"Text can be placed%br%above the top treble clef staff%br%by first increasing the offset for that system/staff%br%and then restoring it for the next system/staff%br%and placing a suitable PageTxtMaestro and PageTxt object."|Fnt:PageText|YLoc:Top|CY:12|XLoc:Center
|Clef|Type:Treble
|Key|Signature:C|Tonic:C
|TimeSig|Signature:4/4
|Note|Dur:4th|Pos:1
|Note|Dur:4th|Pos:0
|Note|Dur:4th|Pos:-1
|Note|Dur:4th|Pos:-2
|Bar
|Note|Dur:4th|Pos:-3
|Note|Dur:4th|Pos:-2
|Note|Dur:4th|Pos:-1
|Note|Dur:4th|Pos:0
|Bar
|Note|Dur:4th|Pos:1
|Note|Dur:4th|Pos:0
|Note|Dur:4th|Pos:-1
|Note|Dur:4th|Pos:-2
|Bar
|Note|Dur:4th|Pos:-3
|Note|Dur:4th|Pos:-2
|Note|Dur:4th|Pos:-1
|Note|Dur:4th|Pos:0
|Bar|SysBreak:Y
|Boundary|Style:Reset
|Note|Dur:4th|Pos:1
|Note|Dur:4th|Pos:0
|Note|Dur:4th|Pos:-1
|Note|Dur:4th|Pos:-2
|Bar
|Note|Dur:4th|Pos:-3
|Note|Dur:4th|Pos:-2
|Note|Dur:4th|Pos:-1
|Note|Dur:4th|Pos:0
|Bar
|Note|Dur:4th|Pos:1
|Note|Dur:4th|Pos:0
|Note|Dur:4th|Pos:-1
|Note|Dur:4th|Pos:-2
|Bar
|Note|Dur:4th|Pos:-3
|Note|Dur:4th|Pos:-2
|Note|Dur:4th|Pos:-1
|Note|Dur:4th|Pos:0
|Bar|SysBreak:Y
|Boundary|Style:NewSize|Upper:50|Lower:6
|Note|Dur:4th|Pos:1
|Note|Dur:4th|Pos:0
|Note|Dur:4th|Pos:-1
|Note|Dur:4th|Pos:-2
|Bar
|Note|Dur:4th|Pos:-3
|Note|Dur:4th|Pos:-2
|Note|Dur:4th|Pos:-1
|Note|Dur:4th|Pos:0
|Text|Text:"Additional text can be placed"|Font:PageText|Pos:41|Justify:Center|Placement:AtNextNote
|Text|Text:"in the middle of a piece using text objects"|Font:PageText|Pos:36.5|Justify:Center|Placement:AtNextNote
|Text|Text:"by first increasing the offset for that system/staff"|Font:PageText|Pos:32|Justify:Center|Placement:AtNextNote
|Text|Text:"and then restoring it for the next system/staff"|Font:PageText|Pos:27.5|Justify:Center|Placement:AtNextNote
|Bar
|Note|Dur:4th|Pos:1
|Note|Dur:4th|Pos:0
|Note|Dur:4th|Pos:-1
|Note|Dur:4th|Pos:-2
|Bar
|Note|Dur:4th|Pos:-3
|Note|Dur:4th|Pos:-2
|Note|Dur:4th|Pos:-1
|Note|Dur:4th|Pos:0
|Bar|SysBreak:Y
|Boundary|Style:Reset
|Note|Dur:4th|Pos:1
|Note|Dur:4th|Pos:0
|Note|Dur:4th|Pos:-1
|Note|Dur:4th|Pos:-2
|Bar
|Note|Dur:4th|Pos:-3
|Note|Dur:4th|Pos:-2
|Note|Dur:4th|Pos:-1
|Note|Dur:4th|Pos:0
|Bar
|Note|Dur:4th|Pos:1
|Note|Dur:4th|Pos:0
|Note|Dur:4th|Pos:-1
|Note|Dur:4th|Pos:-2
|Bar
|Note|Dur:4th|Pos:-3
|Note|Dur:4th|Pos:-2
|Note|Dur:4th|Pos:-1
|Note|Dur:4th|Pos:0
|Bar|SysBreak:Y
|Boundary|Style:Reset
|AddStaff|Name:"Left Hand"|Group:"Standard"
|StaffProperties|EndingBar:Section Close|Visible:Y|BoundaryTop:10|BoundaryBottom:10|Lines:5|Color:Default
|StaffProperties|Muted:N|Volume:127|StereoPan:64|Device:0|Channel:2
|StaffInstrument|Patch:0|Trans:0|DynVel:10,30,45,60,75,92,108,127
|Clef|Type:Bass
|Key|Signature:C|Tonic:C
|TimeSig|Signature:4/4
|Note|Dur:4th|Pos:-1
|Note|Dur:4th|Pos:-2
|Note|Dur:4th|Pos:-3
|Note|Dur:4th|Pos:-4
|Bar
|Note|Dur:4th|Pos:-5
|Note|Dur:4th|Pos:-4
|Note|Dur:4th|Pos:-3
|Note|Dur:4th|Pos:-2
|Bar
|Note|Dur:4th|Pos:-1
|Note|Dur:4th|Pos:-2
|Note|Dur:4th|Pos:-3
|Note|Dur:4th|Pos:-4
|Bar
|Note|Dur:4th|Pos:-5
|Note|Dur:4th|Pos:-4
|Note|Dur:4th|Pos:-3
|Note|Dur:4th|Pos:-2
|Bar|SysBreak:Y
|Note|Dur:4th|Pos:-1
|Note|Dur:4th|Pos:-2
|Note|Dur:4th|Pos:-3
|Note|Dur:4th|Pos:-4
|Bar
|Note|Dur:4th|Pos:-5
|Note|Dur:4th|Pos:-4
|Note|Dur:4th|Pos:-3
|Note|Dur:4th|Pos:-2
|Bar
|Note|Dur:4th|Pos:-1
|Note|Dur:4th|Pos:-2
|Note|Dur:4th|Pos:-3
|Note|Dur:4th|Pos:-4
|Bar
|Note|Dur:4th|Pos:-5
|Note|Dur:4th|Pos:-4
|Note|Dur:4th|Pos:-3
|Note|Dur:4th|Pos:-2
|Bar|SysBreak:Y
|Note|Dur:4th|Pos:-1
|Note|Dur:4th|Pos:-2
|Note|Dur:4th|Pos:-3
|Note|Dur:4th|Pos:-4
|Bar
|Note|Dur:4th|Pos:-5
|Note|Dur:4th|Pos:-4
|Note|Dur:4th|Pos:-3
|Note|Dur:4th|Pos:-2
|Bar
|Note|Dur:4th|Pos:-1
|Note|Dur:4th|Pos:-2
|Note|Dur:4th|Pos:-3
|Note|Dur:4th|Pos:-4
|Bar
|Note|Dur:4th|Pos:-5
|Note|Dur:4th|Pos:-4
|Note|Dur:4th|Pos:-3
|Note|Dur:4th|Pos:-2
|Bar|SysBreak:Y
|Note|Dur:4th|Pos:-1
|Note|Dur:4th|Pos:-2
|Note|Dur:4th|Pos:-3
|Note|Dur:4th|Pos:-4
|Bar
|Note|Dur:4th|Pos:-5
|Note|Dur:4th|Pos:-4
|Note|Dur:4th|Pos:-3
|Note|Dur:4th|Pos:-2
|Bar
|Note|Dur:4th|Pos:-1
|Note|Dur:4th|Pos:-2
|Note|Dur:4th|Pos:-3
|Note|Dur:4th|Pos:-4
|Bar
|Note|Dur:4th|Pos:-5
|Note|Dur:4th|Pos:-4
|Note|Dur:4th|Pos:-3
|Note|Dur:4th|Pos:-2
|Bar|SysBreak:Y
!NoteWorthyComposer-End