my way for this situation:

global gMIAW

on mouseUp me
gMIAW = window("fotosE.dir")
gMIAW.filename = "Whatever"
gMIAW.visible = true
gMIAW.windowType = 2
....
end

-- in that miaw
on mouseDown me
close(gMIAW)
forget(gMIAW)
gMIAW = VOID
end