  Let $\mathfrak{g}'\subset \mathfrak{g}$ be the pair of Lie algebras of either
symplectic or orthogonal infinitesimal endomorphisms of the complex vector
spaces $\mathbb{C}^{N-2}\subset \mathbb{C}^N$ and $U_q(\mathfrak{g}')\subset
U_q(\mathfrak{g})$ the pair of quantum groups with triangular decomposition
$U_q(\mathfrak{g})=U_q(\mathfrak{g}_-)U_q(\mathfrak{g}_+)U_q(\mathfrak{h})$.
Let $Z_q(\mathfrak{g},\mathfrak{g}')$ be the corresponding step algebra and
regard its generators as rational trigonometric functions $\mathfrak{h}^*\to
U_q(\mathfrak{g}_\pm)$. We describe their regularization such that the
resulting generators do not vanish when specialized at any weight.
