I've hand quilted 4 of my quilts now, and I spray basted them all with 505 spray. No problems whatsoever with getting the needle through, so I'd give it a go if I were you! I use quite a lot of spray when I'm basting, so I don't think you'd have any problems with it!

Not me, but I do have a suggestion. Keep an unlit candle next to where you are quilting and poke the needle point into it when the needle resistance occurs. It might work, might not.

Thanks for all your suggestions, think I'll try a sample, as suggested, before spraying the whole thing. And thanks for the link, sounds like it might work. I'm going to try a candle to poke my needle in, but I may have to put my current quilt on hold until I figure out machine quilting.