What is the ruling on pausing at the word "al-ʿālamīn" (the worlds) in the Abrahamic prayer (Salat al-Ibrahimiyya), and does this change the meaning to the extent of reaching disbelief (kufr)?

It is permissible to pause at "al-alamin" (the worlds/all beings) and it is permissible to connect it (to what follows), and there is no harm in either. Pausing at "al-alamin" does not carry an ugly meaning nor does it lead to disbelief. The questioner should beware of falling into obsessive doubts.