A fourth place finish for Singaporean
Three-time Hong Kong Open champion, Shalin tied fourth with another Malaysian, Sharon Koh with 2108 ahead of Chinese Taipei's Tsai Hsin Yi squeezing into the stepladder finals in sixth.
Geraldine Ng, Cherie Tan and Jasmine Yeong-Nathan, who did well in Stage 1, fell by the wayside to end the second round ninth, 11th and eighth positions respectively.
Shalin edged Sharon Koh and Tsai Hsin Yi, 227-224-222 in a thrilling first stepladder match and went on to defeat Hui Fen and second-seed, Sin Li Jane in the second match. Hui Fen never settled down to her usual rythmn with four open frames to end in a disappointing 150.
Du won the first match by defeating fourth-seed Cyrus Cheung of Hong Kong and fifth-seed, Jeri Ramadona of Indonesia, 212-203-199 before crashing out in the second match.
Hussain won HK$55,000 as champion with Zulmazran settling for HK$22,000. Shalin took home HK$28,000 as the women's champion and Zandra settling for HK$12,000. Li Jane and Hui Fen won HK$7,000 and HK$3,500 respectively.