At least one-third party in China has expressed its worries about Microsoft's (NASDAQ:MSFT) planned $69 billion acquisition of videogame giant Activision (NASDAQ:ATVI). The third party expressed its concerns to China's antitrust regulator, the State Administration for Market Regulation, according to a Dealreporter item on Friday. The publication previously reported that two Chinese game operators, including Tencent (OTCPK:TCEHY), were supportive of the transaction. The companies initially filed the transaction with SAMR in April under a "simplified procedure," though they were forced to file it under normal procedure, media outlets reported in November. China is the least worry of investors involved with…