OLC Scoring question

For those that know the finer points..
Question.
I understand to get maximum extra triangle points at the end of your flight you want to cross your release point, or Close Your Triangle.
On my Oudie I have my OLC scored flight displayed with a yellow line, so I can see it in all the other clutter and information displayed.
This summer while flying out of Salida I released and then flew to the clouds about 12 miles south to get to base, then I turned north for my first leg. My Yellow OLC scoring track line started where I turned north.
When I finished my day I flew through the start of this line. Is this where I should have "Closed My Triangle" Or should I have Closed My Triangle where I released from Tow? Where I released from tow that day would have been hard to pinpoint exactly.
So what is it? Start of scored flight or tow release point?
And how close to I need to be to the correct point vertically and horizontally?
Thanks in advance.