Possible Clues:

• Gain control over flowing stream
• Overcome; great artist
• Put 10,000 hours into, it's said
• Male dog owner
• & 22 Who will give instructions to pack up
• Teacher from Michaelmas term
• Original depiction of woman going into labour (it's a boy!)?
• Guru to half of those in 18 across
• Half of 14 across working in classy surroundings
• Get a grip on what Margaret Samuels is concealing in retrospect