Curly bracket for subequation enviroment using the mtpro2 v. lite

Question

Remembering the very nice answer given by the user @Mico, Curly braces using mtpro2[lite]: fix correct alignment, it has been used into an equation the enviroment

\ccases{\begin{aligned}.....\end{aligned}}

(here the complete code)

\documentclass{article}
\usepackage[lite]{mtpro2}
\usepackage{amsmath}

\begin{document}
\[
\ccases{
  \begin{aligned}
    x &= R\sin\theta\cos\varphi\\
    y &= R\sin\theta\sin\varphi\\
    z &= R\cos\theta
  \end{aligned}
}
\quad\text{vs.}\qquad
\begin{cases}
  \begin{aligned}
    x &= R\sin\theta\cos\varphi\\
    y &= R\sin\theta\sin\varphi\\
    z &= R\cos\theta
  \end{aligned}
\end{cases}
\]
\end{document}

to have a very nice curly bracket, as the below image.

But using the enviroment subequation into this MWE,

\documentclass{article}
\usepackage[lite]{mtpro2}
\usepackage{mathtools,newtxtext}
\usepackage{empheq}
\begin{document}
\begin{subequations}
\ccases{\begin{aligned}
A &= B\\
C &= D\\
F &= G \\
H &= I
\end{aligned}
}
\end{subequations}

\end{document}

I have not obtained the curly brace symbol, because I have this warning:

Undefined control sequence. l.7 \cccases {\begin{aligned}

If I use this MWE:

\documentclass{article}
\usepackage[lite]{mtpro2}
\usepackage{mathtools,newtxtext}
\usepackage{empheq}
\begin{document}
\begin{subequations}
\begin{empheq}[left=\empheqlbrace]{align}
A  &= C\\
F &= 0 \\
Ah &= ty\\
qw &= oo
\end{empheq}
\end{subequations}

\end{document}

the code compile correctly but I have not the curly bracket but the classic bracket of a sisteme:

What can be the solution(s) for my problem?