Crossword puzzle clue "casino plays and events that occur as you work your way down through the four sets of circles"

Casino plays ... and events that occur as you work your way down through the four sets of circles

It may straddle neighboring countries ... and, in a different way, what each of four sets of puzzle circles graphically depicts

Car mishaps that occur at this puzzle's four circles

Classic comics catchphrase ... and a hint to four sets of puzzle circles

What's clued in parentheses for each of four answers, and found in corresponding sets of puzzle circles

Program interruptions literally demonstrated by this puzzle's four sets of circles

Opus ___ (Catholic teaching also called "the Work, work work work work")

Angle irons graphically represented by four sets of black squares in this grid, and by letter formations starting in the four longest answers