Nahh, Sonic 2 isn't too hard to port. I've easily ported some background deformation stuff from the Puto's S2K code format, that is much better to understand than the known S2F one.
afaik, S2's and S1's deformation routines are very different, Sonic 1's manager is much easier to learn, Think it's as simple as having it check for what BG line it is and how fast you want it to scroll.
Well, Markey... To be honest, my opinion about the LZ's background is that the art is very beautiful and nicely designed, but until the last SLZ's and MZ's art needs of some piece of redesign and some palette fixes. It's interesting to see new customized backgrounds, I must admit that they are in need of some fix yeah. But the art stuff itself is very professional, wich make me pause the gameplay for appreciate it.
While I'm not sure about your problem, that design is absolutely awesome, much better than what you had before.