Do I have to score point by point?
No. You can score live at the table, or enter the result afterwards. Live scoring is the fuller record and is the only way to get rally-level statistics, since those need the sequence rather than the final score. Both recording modes can contribute to records and statistics once the result is accepted; ratings and individual statistics still follow the game's eligibility rules.
What if my opponent never confirms the result?
If your league asks for confirmation, an unconfirmed result is accepted automatically once the league's confirmation window has passed, so one unresponsive person cannot hold up the standings. A league can also switch confirmation off, in which case results count as soon as they are recorded.
What if we disagree about the score?
Either of you can dispute it. A disputed result is not deleted. It stays on the record and stops counting until it is sorted out.
I recorded the wrong score. Can I fix it?
Yes, within the league's amendment window. After that it needs someone with the right role.
Can someone without an account play?
Yes, as a guest. Once the result is accepted, the game counts towards points and win and loss, but it never moves anyone's rating, including the players who do have accounts.