Hey,
It's too late to tell you this, but I will any way.
You can, and I did, put down a good layer of base rock such as tufa or lace rock, and then stack your good lr on top of that. The stuff on the bottom will die off anyway, and the base rock that ends up being exposed will become lr eventually. That way you can build good caves and such out of the much cheaper rock. The tufa and lace rock I put in my tank last April has coraline growing on it now.
Anyway, since you used cured lr you might want to try a few turbo's and see how they do. As far as the bubble algae goes, get as much out as you can manually, without popping it, and then get some small emerald crabs when you're ready. (They are the only thing I know that eats it.) Also, bubble algae, like any other algae, needs nutrients and light to grow. I would cut back on the lighting photo-period and see if that helps.
Good luck!