Correct for the first statement.
For the second statement, I wish “all posts by trust level 1 and above should not be approved” (this is why in my current settings I put TL1)
Agreed.
I would like all posts by trust level 0 users to require approval—the whole time while they are trust level 0 (not just the first post), so if I understand your instruction, I would put TL1 in that setting is it?