RE: Here's a simple tip!
You can keep them open during use by squeezing the bottle when you pick it up and maintaining that pressure to help regulate the flow while applying the CA. Before sitting the container down, release the pressure to suck the CA out of the tip, therefore keeping the applicator clean. I usually 'pump' the bottle a few times to be sure the tip is cleared.
Never had the problem of the tips not fitting on the bottles though.
Terry in LP