As I interpret this, only trout must be released in the C&R areas. If there are no exceptions for walleye, then state wide regulations would apply as far as length and number you can keep.
" In the following areas, trout must be released immediately. Only artificial lures or flies may be used (natural or scented baits are not allowed). All hooking points must be barbless. Chumming is not allowed. Catching bait with bait tackle is not allowed:"