Had you ever known in bowling to improve your leverage on the floor when you throw, decrease your slide by brushing the slide portion of your shoe with a wire brush from heel to toe. It's something like you need to have less shine to give a more consistent reaction when throwing. Also if you lift or turn your ball during release because it will not hit your target and will likely end up likely as a gutter ball. At all times your shoulders should be kept square to the foul lines. I choose a plastic ball depending on how staright I want it to go for picking up spares since it would be difficult with the big hooking balls Hand position is critical to a proper release and roll. The middle finger of my forearm will be at 6 o' clock all the way through untill I release. I visualize my middle finger going through my target at the moment of release. Just practice this technique without scoring, and you will more likely perfect it irrespective of lane conditions & different balls. If you are serious about excelling yourself in the bowling, I would also advise you to visit
Ultimate Guide To Bowling