Clarification on BoxUpdates Function

The code's somewhat messy but even so it demonstrates an apparent update problem.

;Check the SortJobs routine for the BoxUpdates(1,?) line.
; Try clicking on the Sort Jobs button with the ? set to 1 and set to 2 (or 3).
; Automated it to cycle between 1,1, (1,2), and (1,3) every time you click Sort
errormode(@notify)

:Startup
Gosub InitVars
Gosub LoadBox
Gosub MakeSortedList
Gosub UpdateBox


:MainLoop
While @True
  Gosub CheckButtons
  if UpdateBoxes
    Gosub UpdateBox
    UpdateBoxes = @False
  endif
endwhile
exit



;*******
:LoadBox
;*******
MaxButtons = 2
x1 = 50
x2 = 740
y1 = 50
y2 = 740
BoxesUp("%x1%,%y1%, %x2%, %y2%", @normal)
BoxCaption(1, "%ThisProgName% - loading")
xdiff = x2 - x1
ydiff = y2 - y1
tag1 = "TAG1"
for loop = 1 to MaxButtons
   bd%loop%=loop
next loop
Gosub ResetBoxes
Return

;************
:CheckButtons
;************
;Only 1 button can be pushed at any one time
bpushed = 0
for loop = 1 to MaxButtons
   If BoxButtonStat(1,loop) Then bpushed = loop
next loop
Select bpushed
  case 0   ;No button pushed
     break
  case bd1  ;Sort - open sort box...
     Gosub SortJobs
     break
  case MaxButtons  ;Exit
     query = AskYesNo("Exiting...", "Are you sure you want to quit?")
     if query == @Yes
       exit
     endif
     break
endSelect

Return

;****************
:CheckSortButtons
;****************
     Gosub MakeSortedList
Return

;**************
:MakeSortedList
;**************
sortedList = ""
UpdateBoxes = @True
Return


;********
:InitVars
;********
ThisProgName = "Box Bugs"
SortedList = ""
UpdateBoxes = @True
UpdateBug = 1

Return


;*********
:UpdateBox
;*********
BoxCaption(1, ThisProgName)
BoxDataClear(3, tag1)
BoxDataTag(3, tag1)
BoxUpdates(3,0) ;Delay drawing until end

BoxUpdates(3,2)
Return


;********
:SortJobs
;********
BoxNew(2, "10,10,1000,1000", 2)

;***************
;Confirmed bug
;  Boxes don't open in front the way they are supposed to do, if you use them as I
; have been.
;***************
;Trying open box 3 to display box 2. just might work. Does, mostly
; must kill the buttons on box 1
; must redraw box 1 and 3, reset their text settings, when I'm done with box "2"
BoxNew(3, "10,55,950,600", 1)
BoxDataTag(3, tag1)
BoxUpdates(1, 0)
for a = 1 to MaxButtons
   BoxButtonKill(1, a)
next a
;*************************** following line shows apparent box bug #2.
;If updates is set to 2 or 3, update doesn't take place until screen is covered by
; a separate window. (shows up when window moved off screen, or is resized also)
BoxUpdates(1, updateBug)
if UpdateBug == 1
  Display(2, "Sort and Exit button should come back normally", "")
  UpdateBug = 2
else
  if UpdateBug == 2
    Display(2, "Update set to 2", "Sort and Exit button don't come back until windows tells winbatch to redraw")
    UpdateBug = 3
  else
    Display(2, "Update set to 3", "Sort and Exit button don't come back until windows tells winbatch to redraw")
    UpdateBug = 1
  endif
endif
;***************

BoxUpdates(2,0)
BoxCaption(2, "Sort jobs by...")
BoxUpdates(2,1)
BoxDestroy(2)
Gosub ResetBoxes  ;to get around a bug in WinBatch
Return


;**********
:ResetBoxes
;**********
BoxNew(3, "7,55,993,600", 1)

Black = "0,0,0"
White = "255,255,255"
BoxColor(1, White, 1)
BoxPen(1, Black, 2)
BoxDrawRect(1, "0,0, 1000,1000", 1)
bx1 = 55
bx2 = 135
by1 = 10
by2 = 50
BoxTextColor(1, White)

BoxButtonDraw(1, bd1, "Sort Jobs...", "300,680, 550,730")

BoxButtonDraw(1, bd%MaxButtons%, "Exit", "800,890, 950,990")
BoxDataTag(3, tag1)
Return