I love spray basting, but almost all of us at least start with way too much product. You shouldn't be able to see the spray, or feel it as either damp or cool spots as you are sandwiching.
As Quilting Vagabond suggests, if your needle is gumming up the best thing is simply let everything sit a day or two before going back to work and it should be better.
Sometimes our time crunches don't allow that. In that case, keep some nail polish remover (or rubbing alcohol) and cotton balls and wipe off the needle as needed.
I always wash my quilts before giving them -- I like to have at least a week between my expected done date and the giving date just in case of too much spray. Be warned that if you wash them too gooey you can have problems with lint and such sticking to the quilt top, that can usually be rubbed off or washed again.