Custom beamer blocks for pros and cons list

[Andrés Ramírez]

Hi.

I am adapting this example:
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https://tex.stackexchange.com/questions/28760/custom-beamer-blocks-for-pros-and-cons
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This is my file:
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#+AUTHOR: Me
#+EMAIL:     
#+DATE: 2022
#+DESCRIPTION:
#+KEYWORDS:
#+OPTIONS:   toc:nil
#+EXPORT_SELECT_TAGS: export
#+EXPORT_EXCLUDE_TAGS: noexport

#+startup: beamer
#+LaTeX_CLASS: beamer
#+LATEX_CLASS_OPTIONS: [bigger]
#+BEAMER_FRAME_LEVEL: 2
#+COLUMNS: %40ITEM %10BEAMER_env(Env) %9BEAMER_envargs(Env Args) 
%4BEAMER_col(Col) %10BEAMER_extra(Extra)
#+LaTeX_Header: \beamertemplatenavigationsymbolsempty
#+LaTeX_Header: \newenvironment<>{problock}[1]{%
#+LaTeX_Header:   \begin{actionenv}#2%
#+LaTeX_Header:       \def\insertblocktitle{#1}%
#+LaTeX_Header:       \par%
#+LaTeX_Header:       \mode<presentation>{%
#+LaTeX_Header:         \setbeamercolor{block 
title}{fg=white,bg=orange!20!black}
#+LaTeX_Header:        \setbeamercolor{block body}{fg=black,bg=olive!50}
#+LaTeX_Header:        \setbeamercolor{itemize item}{fg=orange!20!black}
#+LaTeX_Header:        \setbeamertemplate{itemize item}[triangle]
#+LaTeX_Header:      }%
#+LaTeX_Header:       \usebeamertemplate{block begin}}
#+LaTeX_Header:     {\par\usebeamertemplate{block end}\end{actionenv}}
    
** Comparisson
   :PROPERTIES:
   :BEAMER_envargs: [t]
   :END:
*** Pros                                                      :BMCOL:B_block:
    :PROPERTIES:
    :BEAMER_col: 0.45
    :BEAMER_env: block
    :END:
#+begin_problock    
  - New.
  - Other Pro.
  - Additional Pro.
#+end_problock

*** Cons                                                      :BMCOL:B_block:
    :PROPERTIES:
    :BEAMER_col: 0.4
    :BEAMER_env: block
    :BEAMER_envargs: <2->
    :END:

  - Need Testing.
  - Other Con.
  - More Con.
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I am getting an error and PDF is not generated.

Thanks.