This song, "Kotoboa-asobi Uta" requires a time signature of 2/4 + 3/8 of which each measure has both 2/4 & 3/8. I don't think i should type in 7/8 since it's not what was written in the piece. In each measure, it is divided into 2 using a dotted barline, and as normally, each measure is divided by a barline. I want to send a photo to clear things up, but it seems that I can't since I'm not a member.
So basically it looks like this:
2 + 3 ♪ ♫ ♪ <insert a vertical line here> ♪ ♫ <insert barline here>
4 8
that's not the piece itself, but that is what it should look like... I guess. Any feedback will be helpful 
G'day Dominique,
After a short consideration I would approach this thus:
Use a visible 2/4 + 3/8 time sigs., invisible 7/8, use normal plus broken bar lines, use a tempo staff to manage the change in metronome marks that would likely be required to maintain tempo (asuming the beats remain constant), placed between local repeats with the repeat number set to handle all the full bars
Something like this:
!NoteWorthyComposer(2.5)
|Locale|ACP:1252
|Editor|ActiveStaff:2|CaretIndex:1|CaretPos:9
|SongInfo|Title:""|Author:"<Name>"|Lyricist:""|Copyright1:"Copyright © 2012 <Name>"|Copyright2:"All Rights Reserved"
|PgSetup|StaffSize:16|Zoom:4|TitlePage:Y|JustifyVertically:Y|PrintSystemSepMark:N|ExtendLastSystem:N|DurationPadding:Y|PageNumbers:0|StaffLabels:None|BarNumbers:None|StartingBar:1
|Font|Style:StaffItalic|Typeface:"Times New Roman"|Size:10|Bold:Y|Italic:Y|CharSet:0
|Font|Style:StaffBold|Typeface:"Times New Roman"|Size:8|Bold:Y|Italic:N|CharSet:0
|Font|Style:StaffLyric|Typeface:"Times New Roman"|Size:7|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:16|Bold:Y|Italic:N|CharSet:0
|Font|Style:User2|Typeface:"Times New Roman"|Size:8|Bold:N|Italic:N|CharSet:0
|Font|Style:User3|Typeface:"Times New Roman"|Size:8|Bold:N|Italic:N|CharSet:0
|Font|Style:User4|Typeface:"Times New Roman"|Size:8|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:1.27|Top:1.27|Right:1.27|Bottom:1.27|Mirror:N
|AddStaff|Name:"Staff"|Group:"Standard"
|StaffProperties|EndingBar:Section Close|Visible:Y|BoundaryTop:12|BoundaryBottom:12|Lines:5|Color:Default
|StaffProperties|Muted:N|Volume:127|StereoPan:64|Device:0|Channel:1
|StaffInstrument|Trans:0|DynVel:10,30,45,60,75,92,108,127
|Clef|Type:Treble
|Key|Signature:C|Tonic:C
|TimeSig|Signature:2/4
|Text|Text:"+"|Font:User1|Pos:0|Wide:Y
|TimeSig|Signature:3/8
|TimeSig|Signature:7/8|Visibility:Never
|Note|Dur:8th|Pos:-6|Opts:Stem=Up,Beam=First
|Note|Dur:8th|Pos:-5|Opts:Stem=Up,Beam=End
|Note|Dur:8th|Pos:-4|Opts:Stem=Up,Beam=First
|Note|Dur:8th|Pos:-3|Opts:Stem=Up,Beam=End
|Bar|Style:BrokenSingle
|Note|Dur:8th|Pos:-2|Opts:Stem=Up,Beam=First
|Note|Dur:8th|Pos:-1|Opts:Stem=Up,Beam
|Note|Dur:8th|Pos:0|Opts:Stem=Up,Beam=End
|Bar
|Note|Dur:8th|Pos:1|Opts:Stem=Down,Beam=First
|Note|Dur:8th|Pos:0|Opts:Stem=Down,Beam=End
|Note|Dur:8th|Pos:-1|Opts:Stem=Up,Beam=First
|Note|Dur:8th|Pos:-2|Opts:Stem=Up,Beam=End
|Bar|Style:BrokenSingle
|Note|Dur:8th|Pos:-3|Opts:Stem=Up,Beam=First
|Note|Dur:8th|Pos:-4|Opts:Stem=Up,Beam
|Note|Dur:8th|Pos:-5|Opts:Stem=Up,Beam=End
|Bar
|Note|Dur:Half|Pos:-6
|Bar|Style:BrokenSingle
|Rest|Dur:4th,Dotted
|AddStaff|Name:"Staff-1"|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|Trans:0|DynVel:10,30,45,60,75,92,108,127
|TimeSig|Signature:7/8
|Bar|Style:LocalRepeatOpen
|Tempo|Tempo:120|Pos:9
|Rest|Dur:8th
|Rest|Dur:8th
|Rest|Dur:8th
|Rest|Dur:8th
|Tempo|Base:Eighth|Tempo:120|Pos:9
|Rest|Dur:8th
|Rest|Dur:8th
|Rest|Dur:8th
|Bar|Style:LocalRepeatClose|Repeat:3
!NoteWorthyComposer-End
There may be better methods, but this would likely cover your needs.