Beamerposter 问题：无法找到 Runaway 参数

Question

我正在尝试学习如何在共享 latex 上使用 beamerposter。我创建了一个共享 latex 文件，并复制了http://users.umiacs.umd.edu/~jiarong/poster/icml12-inferning/styles/beamerthemeconfposter.sty放入文件 beamerthemeconfposter.sty。然后我在主 tex 文件中生成了此问题底部的代码，但出现了以下错误：

 Runaway argument? main.tec, line 29
 { \end {minipage} \end {center} \end {beamercolorbox} \end {beamercol\ETC. 
 !File ended while scanning use of \beamer@sbtexec. 
 <inserted text>      
          \par 
 I.29 \usetheme{confposter} 
 I suspect you have forgotten a '}', causing me to read past where you              
 wanted me to stop.

这是我在 main.tex 文件中输入的代码：

\documentclass[final]{beamer}

\usepackage[scale=1.24]{beamerposter} 

\usetheme{confposter}
\usepackage{exscale} 
\setbeamercolor{block title}{fg=green,bg=white} 
\setbeamercolor{block body}{fg=black,bg=white} 
\setbeamercolor{block alerted title}{fg=white,bg=dblue!70} 
\setbeamercolor{block alerted body}{fg=black,bg=dblue!10} 

\newlength{\sepwid}
\newlength{\onecolwid}
\newlength{\twocolwid}
\newlength{\threecolwid}
\setlength{\paperwidth}{48in} 
\setlength{\paperheight}{36in} 
\setlength{\sepwid}{0.024\paperwidth} 
\setlength{\onecolwid}{0.22\paperwidth} 
\setlength{\twocolwid}{0.464\paperwidth} 
\setlength{\threecolwid}{0.708\paperwidth} 
\setlength{\topmargin}{-0.5in} 
%-----------------------------------------------------------

\usepackage{graphicx} 
\usepackage{booktabs} 

%----------------------------------------------------------------------------------------
%   TITLE SECTION 
%----------------------------------------------------------------------------------------

\title{Oh well} 

\author{Oh well} 

\institute{Oh well} 

%----------------------------------------------------------------------------------------

\begin{document}

\begin{frame}

Oh well.

\end{frame}

\end{document}

有人知道如何解决这个问题吗？