Drop Down Menu Options?

Big thanks to groups user huntermcg for this find.

I have entered this into my "ThisWorkbook" -

Private Sub Workbook_Open()
Dim sh As Object

On Error Resume Next
Application.CommandBars("Navigate XL-Dennis").Delete
Application.CommandBars("Navigate Sheets").Delete
On Error GoTo 0

With Application.CommandBars.Add("Navigate Sheets", , False, True)

With .Controls.Add(msoControlButton)
.TooltipText = "Move Back"
.FaceId = 1017
.OnAction = "Move_Back"
.BeginGroup = True
End With

With .Controls.Add(msoControlDropdown)
For Each sh In ThisWorkbook.Sheets
.AddItem sh.Name
Next sh
.TooltipText = "SheetNavigate"
.OnAction = "Sheet_Navigate"
End With

With .Controls.Add(msoControlButton)
.TooltipText = "Move next"
.FaceId = 1018
.OnAction = "Move_Next"
End With

.Protection = msoBarNoCustomize
.Position = msoBarFloating
.Visible = True
End With
End Sub

and then I entered this into a module -

Private Sub Sheet_Navigate()
Dim stActiveSheet As String

With CommandBars.ActionControl
stActiveSheet = .List(.ListIndex)
ThisWorkbook.Sheets(stActiveSheet).Activate
End With
End Sub

Private Sub Move_Back()
On Error Resume Next
ActiveSheet.Previous.Select
End Sub

Private Sub Move_Next()
On Error Resume Next
ActiveSheet.Next.Select
End Sub

This created a neat little drop down menu for sheet navigation.
(thanks to Bob Phillips for the code at
http://www.excelforum.com/newreply.p...te=1&p=1358771)

QUESTION -

I've applied this to a project of mine and it works great.

Although with my project I have a workbook with over 250 sheets :-)

Is their a way to limit the amount of sheets displayed in the drop
down box?

also if the above is possible...

Is their a way to have different set of sheets displayed for each
worksheet?

For example, on "sheet 1", the drop down only displays sheets 2-5.
Upon the users arrival to sheet 4, the drop down menu displays sheets
30-50.

Thanks for the help in advance.