Sink or Swim (Meta Cryptic, See Instructions)

In the central 5x5 diagram, one letter from each column has floated up out of the grid and into the space above, where it forms part of an appropriate word at 1A. Meanwhile, another letter from each column has sunk down out of the grid and into the space below, forming part of a similarly appropriate word at 9A. It is necessary to determine and properly move these letters in order to make the Down answers fit into the diagram.

But that's not all! The ten unchecked, circled letters in the central diagram can be rearranged to form two five letter words that serve as the answers to the following clues:

These two words are the answer to the meta puzzle (submit both words, in either order, with or without a space in between - the answer is not case-sensitive). However, solving them early may prove helpful in completing the main puzzle.

Good luck! Don't be discouraged - the grid is tough, but most of the clues are quite easy.