1)
What is "Mishtach Charamim"?
1.
Rashi: Fishermen will spread their nets on the rock to dry them. Radak ? "vechi'Soch ha'Mayim ha'Rabim" (19) will be temporary, when the sea rises against it and floods it. The sea will return to its place, and the rock will be dry.
2)
What is "l'Vaz l'Goyim"?
1.
Malbim: Before it will be flooded, Goyim will plunder it ? everyone will take for himself.