  In this paper, we recall Lepowsky's and Wakimoto's product character formulas
formulated in a new way by using arrays of specialized weighted crystals of
negative roots for affine Lie algebras of type $C_l^{(1)}$, $D_{l+1}^{(2)}$ and
$A_{2l}^{(2)}$. Lepowsky-Wakimoto's infinite periodic products appear as one
side of (conjectured) Rogers-Ramanujan-type combinatorial identities for affine
Lie algebras of type $C_l^{(1)}$.
