Possible Clues:

• Terpsichorean activity
• Leader of Conservatives in European spin?
• Word that can follow the ends of 17-, 21-, 36-, 44-, 54- and 64-Across
• Do a quickstep
• Cotillion, for example
• Ball; hop
• Have this hop with a bun, that's plenty
• At tea be there for the start of the hop
• Old invader grasps top of cannon ball
• See 4