Does Tong Xue know the house she designed belongs to Shaoqian? Does Shaoqian know Tong Xue has feelings for him?
Yes, it's implied that Tong Xue knew Shaoqian is the homeowner. Someone asked the scriptwriter this question. The scriptwriter replied that at first, she didn't intend to let Tong Xue know the homeowner was Shaoqian, and everything she did with the house was just her own subconscious doing. Somehow later on, she also felt Tong Xue somehow knew anyway based on her email correspondences with "Professor Chen." I don't know how the heck she found out, but it's pretty evident that she knew since she came back to look at the house one last time before her departure. As for Shaoqian, he probably felt Tong Xue's feelings for him due to several clues:
1. She left the kaleidoscope that her father made her on the baby's crib. The kaleidoscope is like a family heirloom - first given to TongXue, then to her little cousin, and now left to the unborn baby that Tong Xue lost. This baby room and the kaleidoscope prove to Shaoqian that Tong Xue did not purposely abort their baby as she first claimed. She had wanted the baby as much as Shaoqian did