Park at the Sugarbowl. It won't be a problem. The machines are not set up for overnight parking and the forestry have previously suggested buying 2 day tickets.
The no overnight parking is aimed at campervans / motorhomes and people camping in the car park or next to it. The forestry wish to put a stop to this.
Leaving your car to go camping or bothying far away in the hills is not an issue but it would help if this was made clear.
Possibly deliberately vague