Some owners of flats at Wuhan Optics Valley, which is part of the mixed-use development’s second phase, complained of “cracks and leaks” caused by poor workmanship, substandard materials and discrepancies between blueprints and actual features, according to a letter sent by a representative. The letter was accompanied by a dossier of photographs and slides. In early January, angry owners also protested at the project’s handover sales office and demanded an answer from Shui On.