LibTech rocker board. I understand its harder to carve with this board.
Is this difficulty typical for a rocker board
Actually, this is not correct. There's a difference between a board is "easy" to carve and "good" at carving. Every board with a sidecut will carve.
Your board probably is "easy" to carve, i.e. leave a nice pencil line, it just isn't a very good carver cos it won't offer the attributes which ppl seek who are into carving (acceleration throught the carve, pop out of the turn, stiffer flex to hold through high speed carves).
A board which is called "good" at carving will have pop out of the carve, will hold a carve at high speed with a lot of pressure affecting on its flex. They are generally stiffer and thus actually "harder" to carve. More precision and effort (muscle or speed) needed to bend them into the radius and tilt here they'll glide nicely through a trench.
Anyway... you're the one with the max fwd lean highback? I assume that you've some basics not set yet. Full fwd lean is pretty unusual. You either have a fundamental weight distribution issue or ride a board way
too wide for you to "need" the leverage of full fwd lean. Too much weight on front leg is rather unusual; most have too much on the back leg. Stiff straight knees and counter rotation are another main reasons for troubles with turns. Easy going carving at moderate cruising speed with a well sized mid flex board sould be doable with minor movements of your toes/ancles.
Take a lesson or post a vid. Also search for the "creepy basement vid" thread to check if your basic body position is ok.