Try the enclosed centered.inc, I have changed all of the templates to incorporate translation for the infowindow text but it seems I've made a mistake in this one and removed a closing bracket.
For the other problem, I have added that as a needed fix for API v2 and it turns out it doesn't even work because of all the changes Google has made 
so bottom line is those line can be removed in MapHeader.tpl: (see enclosed file)
var tooltip = document.createElement("div");
map.getPane(G_MAP_FLOAT_PANE).appendChild(tooltip);
tooltip.style.visibility="hidden";
NOTE: remove the .txt extension on those files 
-------------------------
The Termite 