Try to create a library Test with a simple Dialog1
In the dialog create a ComboBox ( that's dropdown as default )
Use follow code to creates 3000 items in the combo
The combo has to be the first in the order so when the dialog
starts the combo has the keyboard focus
Start the dialog, then try to use PageDOWN ( without opening the dropdown list
), works ? for me no, I you try to use DOWN key sometimes, this works, but
when you try PageDOWN now, you get an UP key behavior.
Right, this bug doesn't happen if you open the dropdown list before
testing this thing.

Last note: this test is done using addItems with a variant array dimensioned
variable.

THE CODE:

REM  *****  BASIC  *****

Sub Main
	Dim dialog1 As Object
	dialog1 = LoadDialog( "Test", "Dialog1" )
	
	Dim combo As Object
	combo = dialog1.getControl( "combo" )
	
	Dim items As Variant
	Dim i As Long
	
	items = DimArray( 3000 - 1 )
	
	For i = 0 To ( 3000 - 1 )
		items( i ) = "item_" + Format( i, "0" )
	Next i
	
	combo.addItems( items, 0 )
	
	dialog1.Execute()
End Sub

Function LoadDialog(Libname as String, DialogName as String, Optional
oLibContainer)
Dim oLib as Object
Dim oLibDialog as Object
Dim oRuntimeDialog as Object
If IsMissing(oLibContainer ) then
oLibContainer = DialogLibraries
End If
oLibContainer.LoadLibrary(LibName)
oLib = oLibContainer.GetByName(Libname)
oLibDialog = oLib.GetByName(DialogName)
oRuntimeDialog = CreateUnoDialog(oLibDialog)
LoadDialog() = oRuntimeDialog
End Function