simply recurse on all buttons of optiongroup and recalculate each top by eliminating that whose invisible.
if button option is disabled(enabled=.f.) make it visible=.f. (if dont want to see it)
this is a test form for this solution (15 options : some options are invisible,another are disabled..)
can rearrange the optionGroup dynamically from the relative button.

publi oform
oform=newObject("asup")
oform.show
read events
retu
*
DEFINE CLASS asup AS form
	BorderStyle = 0
	Top = 0
	Left = 45
	Height = 312
	Width = 276
	ShowWindow = 2
	Caption = "Form1"
	MaxButton = .F.
	BackColor = RGB(212,210,208)
	Name = "Form1"

	ADD OBJECT optiongroup1 AS optiongroup WITH ;
		AutoSize = .T., ;
		ButtonCount = 15, ;
		BackStyle = 0, ;
		BorderStyle = 0, ;
		Value = 1, ;
		Height = 293, ;
		Left = 28, ;
		Top = 11, ;
		Width = 78, ;
		Name = "Optiongroup1", ;
		Option1.Caption = "Option1", ;
		Option1.Value = 1, ;
		Option1.Height = 17, ;
		Option1.Left = 5, ;
		Option1.Top = 5, ;
		Option1.Width = 61, ;
		Option1.Name = "Option1", ;
		Option2.Caption = "Option2", ;
		Option2.Enabled = .F., ;
		Option2.Height = 17, ;
		Option2.Left = 5, ;
		Option2.Top = 24, ;
		Option2.Width = 61, ;
		Option2.Name = "Option2", ;
		Option3.Caption = "Option3", ;
		Option3.Height = 17, ;
		Option3.Left = 5, ;
		Option3.Top = 43, ;
		Option3.Width = 61, ;
		Option3.Name = "Option3", ;
		Option4.Caption = "Option4", ;
		Option4.Height = 17, ;
		Option4.Left = 5, ;
		Option4.Top = 62, ;
		Option4.Width = 61, ;
		Option4.Name = "Option4", ;
		Option5.Caption = "Option5", ;
		Option5.Height = 17, ;
		Option5.Left = 5, ;
		Option5.Top = 81, ;
		Option5.Visible = .F., ;
		Option5.Width = 61, ;
		Option5.Name = "Option5", ;
		Option6.Caption = "Option6", ;
		Option6.Height = 17, ;
		Option6.Left = 5, ;
		Option6.Top = 100, ;
		Option6.Visible = .F., ;
		Option6.Width = 61, ;
		Option6.Name = "Option6", ;
		Option7.Caption = "Option7", ;
		Option7.Height = 17, ;
		Option7.Left = 5, ;
		Option7.Top = 119, ;
		Option7.Width = 61, ;
		Option7.Name = "Option7", ;
		Option8.Caption = "Option8", ;
		Option8.Height = 17, ;
		Option8.Left = 5, ;
		Option8.Top = 138, ;
		Option8.Visible = .F., ;
		Option8.Width = 61, ;
		Option8.Name = "Option8", ;
		Option9.Caption = "Option9", ;
		Option9.Height = 17, ;
		Option9.Left = 5, ;
		Option9.Top = 157, ;
		Option9.Width = 61, ;
		Option9.Name = "Option9", ;
		Option10.Caption = "Option10", ;
		Option10.Height = 17, ;
		Option10.Left = 5, ;
		Option10.Top = 176, ;
		Option10.Width = 68, ;
		Option10.Name = "Option10", ;
		Option11.Caption = "Option11", ;
		Option11.Height = 17, ;
		Option11.Left = 5, ;
		Option11.Top = 195, ;
		Option11.Width = 68, ;
		Option11.Name = "Option11", ;
		Option12.Caption = "Option12", ;
		Option12.Height = 17, ;
		Option12.Left = 5, ;
		Option12.Top = 214, ;
		Option12.Width = 68, ;
		Option12.Name = "Option12", ;
		Option13.Caption = "Option13", ;
		Option13.Enabled = .F., ;
		Option13.Height = 17, ;
		Option13.Left = 5, ;
		Option13.Top = 233, ;
		Option13.Width = 68, ;
		Option13.Name = "Option13", ;
		Option14.Caption = "Option14", ;
		Option14.Height = 17, ;
		Option14.Left = 5, ;
		Option14.Top = 252, ;
		Option14.Width = 68, ;
		Option14.Name = "Option14", ;
		Option15.Caption = "Option15", ;
		Option15.Enabled = .F., ;
		Option15.Height = 17, ;
		Option15.Left = 5, ;
		Option15.Top = 271, ;
		Option15.Width = 68, ;
		Option15.Name = "Option15"

	ADD OBJECT command4 AS commandbutton WITH ;
		Top = 12, ;
		Left = 120, ;
		Height = 27, ;
		Width = 84, ;
		Caption = "Arrange", ;
		Name = "Command4"

	PROCEDURE Destroy
		clea events
	ENDPROC

	PROCEDURE command4.Click
		create cursor ycurs (num i)

		with thisform.optionGroup1

		for i=1 to .buttonCount
		if .buttons(i).enabled=.f.
		.buttons(i).visible=.f.
		endi

		if .buttons(i).visible=.t.
		insert into ycurs values (i)
		endi
		endfor
		*brow

		local m.xtop,m.rec,m.num0
		m.xtop=10
		local m.xspace
		m.xspace=2    &&spacing between 2 options

		sele ycurs
		scan  
		rec=recno()
		if m.rec=1
		.buttons(num).top=xtop
		else
		go m.rec-1
		m.num0=num
		go rec
		.buttons(num).top=.buttons(m.num0).top+.buttons(m.num0).height+m.xspace
		endi
		endscan

		endwith
	ENDPROC

ENDDEFINE
*
*-- EndDefine: asup