* TSX down 69.62 points, or 0.37 percent, to 12,293.78 * Spain optimism fades, U.S. data reminds of slow global growth * RIM jumps 13 pct after narrower-than-expected loss * Index on track for Q3 gain of 6 percent By Alastair Sharp TORONTO, Sept 28 (Reuters) - Canada's main stock index fell on Friday as investors locked in gains on the last day of the quarter amid concern about instability in Spain, though shares of Research In Motion Ltd surged after its results. Spain's borrowing costs rose back above 6 percent as optimism about the country's debt-fighting plans faded and ahead of the results of a stress test of its crippled banks, while business activity in the U.S. Midwest shrank for the first time since September 2009. "There is a hot and cold sense to what's going on in Europe. They're taking two steps forward and one step back," said Paul Harris, portfolio manager at Avenue Investment Management. "That kind of volatility definitely affects what's going on in the rest of the world." "The other thing is numbers coming out of the U.S.; some of them are good, some of them are bad, all it amounts to is relatively slow growth," Harris said. By 10:45 a.m. (1445 GMT) the Toronto Stock Exchange's S&P/TSX composite index had lost 69.62 points, or 0.37 percent, to 12,293.78, putting it on track for a 6 percent gain for the third quarter. Losses were broad, with energy and banking stocks weighing most heavily. Canadian Natural Resources fell 1.8 percent to C$30.27 and Royal Bank of Canada was off 0.7 percent at C$56.30. By far the most positive story was RIM, which jumped 13 percent to C$7.86. It surprised a pessimistic audience after the close of trading Thursday with news of a bigger cash pile and a smaller-than-anticipated loss, and said it had beat revenue and shipment expectations thanks to strong BlackBerry sales in emerging markets such as Indonesia and India.