I've read about two different ways to put in an overlap liner. The first way (which seems to make the most sense to me) is to hang it similar to a unibead in that it will drape and "fit" along the walls. Then with the shop vac we pull out the wrinkles and start filling. Another way I saw was to sort of stretch it over the top and let it "pull" over the walls as it fills. While that seems like it would create a nice smooth wall, I'm not so sure how it wouldn't buckle the walls or even pull the liner all the way in.
Any advice? We have two weeks before the parts are in but then we are in high speed as it is my child wants to swim for her birthday (unless we put heated water in, I don't think we can warm it that fast!).
Also if anyone has the "waterfall" liner, let me know, I'd like to see pics.