UK Stocks-Factors to watch on Sept. 30

Sept 30 (Reuters) - Britain's FTSE 100 index is seen opening down 0.9 percent on Friday, according to financial bookmakers. * The UK blue chip index closed up 1 percent on Thursday at 6,919.42, boosted by heavyweight oil companies after a decision by OPEC to curb output for the first time since 2008. * GULF KEYSTONE: Gulf Keystone Petroleum, one of the foreign oil firms present in Iraqi Kursdistan, has received a long-awaited $15 million payment from the Kurdistan Regional Governme