CambridgeUS uses the defaulttitle page template which inserts the title graphic at the end; you can redefine the template to include it before the title, and then use
\titlegraphic{\includegraphics[<options>]{image}}
A complete example, including your settings from the linked question:
\documentclass{beamer}
\usetheme{CambridgeUS}
% Set Color ==============================
% Custom colors
\usepackage{xcolor}
% http://www.computerhope.com/htmcolor.htm
\definecolor{gold}{HTML}{FDD017}
\definecolor{deep sky blue}{HTML}{3BB9FF}
\definecolor{light sky blue}{HTML}{82CAFA}
\definecolor{mybackground}{HTML}{82CAFA}
\definecolor{myforeground}{HTML}{0000A0}
\setbeamercolor{normal text}{fg=black,bg=white}
\setbeamercolor{alerted text}{fg=red}
\setbeamercolor{example text}{fg=black}
\setbeamercolor{background canvas}{fg=myforeground, bg=white}
\setbeamercolor{background}{fg=myforeground, bg=mybackground}
\setbeamercolor{palette primary}{fg=black, bg=gray!30!white}
\setbeamercolor{palette secondary}{fg=black, bg=gray!20!white}
\setbeamercolor{palette tertiary}{fg=black, bg=gold}
\setbeamercolor{frametitle}{fg=cyan!80!black}
\setbeamercolor{title}{fg=cyan!80!black}
\setbeamertemplate{headline}
{
\leavevmode%
\hbox{%
\begin{beamercolorbox}[wd=.5\paperwidth,ht=2.65ex,dp=1.5ex,center]{section in head/foot}%
\usebeamerfont{section in head/foot}\insertsectionhead\hspace*{2ex}
\end{beamercolorbox}%
\begin{beamercolorbox}[wd=.5\paperwidth,ht=2.65ex,dp=1.5ex,center]{subsection in head/foot}%
\usebeamerfont{subsection in head/foot}\hspace*{2ex}\insertsubsectionhead
\end{beamercolorbox}}%
\vskip0pt%
}
\makeatletter
\defbeamertemplate*{title page}{mydefault}[1][]
{
\vbox{}
\vfill
\begin{centering}
{\usebeamercolor[fg]{titlegraphic}\inserttitlegraphic\par}
\begin{beamercolorbox}[sep=8pt,center,#1]{title}
\usebeamerfont{title}\inserttitle\par%
\ifx\insertsubtitle\@empty%
\else%
\vskip0.25em%
{\usebeamerfont{subtitle}\usebeamercolor[fg]{subtitle}\insertsubtitle\par}%
\fi%
\end{beamercolorbox}%
\vskip1em\par
\begin{beamercolorbox}[sep=8pt,center,#1]{author}
\usebeamerfont{author}\insertauthor
\end{beamercolorbox}
\begin{beamercolorbox}[sep=8pt,center,#1]{institute}
\usebeamerfont{institute}\insertinstitute
\end{beamercolorbox}
\begin{beamercolorbox}[sep=8pt,center,#1]{date}
\usebeamerfont{date}\insertdate
\end{beamercolorbox}\vskip0.5em
\end{centering}
\vfill
}
\setbeamertemplate{title page}[mydefault][colsep=-4bp,rounded=true,shadow=\beamer@themerounded@shadow]
\makeatother
% Set Color ==============================
\title{Title1}
\subtitle{Title2}
\author{Author}
\institute{Institute}
\date{Date}
\titlegraphic{\includegraphics[height=2cm]{ctanlion}}
\begin{document}
\frame{\maketitle}
\section[Outline]{}
\frame{\tableofcontents}
\section{Header1}
\subsection{Header2}
\frame{\frametitle{Topic1}
%
HTML color codes are the \textbf{hexadecimal triplets} representing the colors red, green, and blue.
%
These color codes can be used to change the color of the background, text, and tables on a web page.
}
\end{document}
To remove the vertical size of the logo use \raisebox{-\height}[0pt][0pt]{\includegraphics[<options>]{<filename>}} The -\height also pushes it downwards from the headline. You can also place this code in a \rlap{..} to also remove the horizontal size.
However, this will not solve your other issue with the title overlapping the logo. In this case I would place the logo somewhere else instead. Also you can use the textpos package or the overlay option of tikz to place the logo on an absolute place of the slide, as shown in How can I position an image in an arbitrary position in beamer?. This must then be done after the title is placed, in the footer maybe, so that it is in the foreground.
Best Answer
CambridgeUS
uses thedefault
title page
template which inserts the title graphic at the end; you can redefine the template to include it before the title, and then useA complete example, including your settings from the linked question: