ROUNDING THIRD by Richard Dresser is the first of our OCTOBER special weekend shows. Performed as an off-Broadway-type "black box" production with scripts-in-hand. Rounding Third describes the humorous journey of two Little League coaches through an entire season, from their first tentative meeting to the climactic championship game. Don is the tough, blue-collar, win-at-all-costs veteran coach whose son is the star pitcher. Michael is a newcomer both to the town and to baseball. He's a corporate executive who agrees to…