Possible Clues:

• It's not hard to smile awkwardly around Penny
• Not complex, complicated or involved
• If the other crossword isn't finished it's not difficult to see why
• Easy as pie
• 5 down in the herb-garden
• Hardly complicated
• It's not hard so to smile around the piano
• Not 19 down enough to make one smile around the piano
• A piece of cake
• Easy to understand