First of all - Wellcome.
Second - you can't flash C902 for free , but you can change firmware with SEUS (Sony Ericsson Update Service) and little help of this [Debrand] A2 (Db3150) Tutorial - Top Sony Forums or you can upload ZH.lng and ZH.T9 with w910i change language - Top Sony Forums and a2uploader you will find here a2uploader - Top Sony Forums