I still have the niggling feeling in the back of my mind which puts the breaks on my game a bit.

I dont feel confortable using some of the canned openers and the only time I feel comfortable approaching is when I actually have a purpose to do so. I feel it has to be a situational openers I use or else it seems very unnatural. I do quite alot of approaches but my chances slip because I cant think of a relevant thing to say in order to approach or open contact - especially on a dance floor.

Should I start having canned material to get over this? Im about half way through the Vin Di Carlo's Seduction Code - hopefully this will help me a bit.

I'm pretty new at this myself however I always open using a situational opener for exactly the same reason as yourself. I normally pick something out of the environment so if its gorgeous out, make that statement and lead into a question. If I'm absolutly stuck for something to say I just open with "Hey hows your day going" and smile.

Seriously I've noticed that the first thing you say to a girl doesn't actually matter, (within reason ofc) its all the stuff that comes after it thats important. If your finding it hard to hook just throw a compliment in there, my personal experience is this works really well and the target opens up a lot easier.

Anyway the point im trying to make is it doesnt matter what you do to get the attention, its what you do with the attention afterwards thats the deal maker.

You are absolutely right there, dude.