FIXME: Corrects the vertical offset in the title frame

Just a hack as I did not find the proper way to remove the vertical
offset in a supposed empty frame

texinputs/beamerthemetptng.sty

@@ -460,6 +460,9 @@
 \defbeamertemplate*{title page}{tpt default}%
 {%
    \thispagestyle{empty}%
+   %FIXME: Hack ... how to remove the vertical offset here??
+   % logoskipv -> pure luck
+   \vskip -\logoskipv%
    \begin{columns}
    \begin{column}{.4\paperwidth}
       \begin{minipage}[t][\paperheight][t]{\textwidth}%