This is the winapi declaration to make a windows topmost on visual basic 6. I think it should be easy for you to convert it to BlitzMax. I think Long integers on Visual basic 6 were 32 bits, so you should consider this longs as integers on blitzmax (I think)
Private Declare Function SetWindowPos Lib "user32" (ByVal hWnd As Long, ByVal iWndInsertAfter As Long, ByVal x As Long, ByVal y As Long, ByVal cx As Long, ByVal cy As Long, ByVal wFlags As Long) As Long
Private Const SWP_NOMOVE = 2
Private Const SWP_NOSIZE = 1
Private Const HWND_TOPMOST = -1
Private Const HWND_NOTOPMOST = -2
Private Const FLAGS = SWP_NOMOVE Or SWP_NOSIZE
this was a typic call to make a window topmost:
SetWindowPos(hWnd, HWND_TOPMOST, 0, 0, 0, 0, FLAGS)
to the transparency thing of the window, I think there was a blitzmax sample on the maxgui forum, take a look.