Usually very quick but obviously things like stewards, delays etc can all slow down settlement. Guess a lot depends on just how bad a race or two affects your strategy, never the best strategy to depend on a previous result if you're betting a race at a time.
You could aways log the race results if you want to see if the previous race has been settled before placing bets, just use the bet logging results sheet
http://www.gruss-software.co.uk/Betting ... esults.htm and monitor the sheet for RESULT_NOT_AVAILABLE or you can just simply check your balance in cell I2/J2 and see if there's enough of a balance to place your bets. Then either reduce your stake so you don't miss out or wait till it is enough to carry on or not.