I had heard from someone no water changes until cycled, then water changes (50%) to get the nitrates down. I also heard that some commercial substrates leach ammonia.
If you put in a lot of stem plants, they will consume the ammonia. Make sure you have enough circulation in the tank and adequate lighting. I like to see well-defined shadows on the substrate, but with the floaters you may not see that. Floaters are very good for CO2, possibly ammonia removal.
I had some luck with API Quick Start. I would use it again, particularly since you've used R/O water - no bacteria in there. It seems to me you're doing too much with the tank. I think you're supposed to just let it sit and test it. However, you may have a special case with your substrate. Sorry I can't give you a more conclusive answer. It seems weird to me, but in the final analysis, I would follow the directions for the substrate. You might check their site for more information. Sorry if I'm a little scattered.