When boiling ribs before cooking them you should boil the ribs until the ribs become slightly soft but not soft enough to where they fall apart.
It should take 25 to 30 minutes of boiling the ribs for them to become soft enough and then you can cook the ribs on the grill.
When cooking ribs on the grill you should put the meatier side down on the grill and then let it cook on the grill for 10 minutes and then brush the ribs with some glaze and grill for another 3 minutes.
Then flip the ribs over and grill the other side for another 10 minutes or until they're fully cooked.