By Clare Jim and Jason Xue HONG KONG (Reuters) -China Evergrande Group said on Wednesday it aims to have a preliminary restructuring proposal in place within six months as the debt-laden developer scrambles to reassure creditors spooked by defaults since its finances began to unravel last year. The long-awaited communication came against the backdrop of Beijing tightening control over the property developer, while taking measures to stabilise China’s crisis-hit property sector. But some bondholders said they were disappointed by the 25-minute call with creditors, which included prepared answer…