Race one, on Saturday, was dominated by the Team Indonesian pair of Sucipt Topan and Wawan Hermawan, who finished first and second respectively while Biddle had to settle for 11th overall.
Biddle suffered bad luck the following morning during the warm-up session before the second race, crashing the bike when her side-stand dug into the track surface.
The accident was soon forgotten, however, and she dusted herself off to reach the start line and then found herself in ninth position after the first lap.
At the end of the second lap, she had dropped to 11th but she fought back up to tenth and then inherited ninth spot when a rider ahead of her fell off. Biddle remained in ninth place until the chequered flag.
"The racing was pretty hectic. It was just a matter of using my race craft, getting my elbows out and making myself as wide as possible," she said.
The next round of the series is set for Circuit Taipei in Taiwan on October 23, with the fourth and final round in Thailand in November. At this stage, Biddle has no plans to be involved in those races. "This trip to Sugo is just for the experience really. It is my off-season at the moment," she said.