1) Then you'll need to designate another way such as via the HUD when a bomb is selected (TDC depress with TDC assigned to HUD) or, when it's out, the TGP and later A/G radar etc.
2) The laser is for the bomb's guidance, the aircraft itself doesn't see it. Operationally, using an LGB is the same as a dumb bomb, minus entering the code.
3) Because the ASL appears only when an A/G TGT is designated because AUTO bombing mode uses the A/G TGT.