I am having the same problem. I copied the line the adobe help says to add to the language.xml file exactly as it says - I didn't even customize the text yet, I just left it as "Your_Text" to see if that would show up. It doesn't, and when I try to open the language.xml file I get the below error. I don't know a lot about programming, but I would think by adding the line that the help link says to add it shouldn't throw this type of error. Maybe we need to add something else having to do with the uitext name tag?
The XML page cannot be displayed
Cannot view XML input using XSL style sheet. Please correct the error and then click the Refresh button, or try again later.
A string literal was expected, but no opening quote character was found. Error processing resource 'file:///C:/Documents an...
<uitext name=”ADOBE_PRESENTER” value=”Your_Text”/> -------------^
i think i found a reference here in the forums: http://forums.adobe.com/message/910903#910903
i was copying and pasting the line of code for the language.xml file from the adobe help directly. seems like notepad doesn't like the formatting, so instead you should type anew in notepad. one of the replies in the forum above gives a good example of exactly where to add the code in the language file, too. seems like that matters, and it is not something the help document talks about.
after i did that i resaved and reuploaded my presentation (we use connect). the first time i played it the custom text didn't appear (actually, no text appeared) but the second time it did!
thanks to those who helped in the above linked forum.