I have been trying to sort out why I can't get the FindReplace piece to work--I have done the iconv work and confirmed the class() of my tweet text (despite the error it is DEFINITELY "character", so are the columns in your spreadsheets), but I keep getting this error:
Error: text is not a character string or factor. Please convert to a character string or factor and then rerun.
In addition: Warning message:
In if (!(class(data[, Var]) %in% c("character", "factor"))) { :
the condition has length > 1 and only the first element will be used
I don't suppose you've seen this? Google searches haven't turned up anything particularly useful and it's blocking me from trying out your cool mapping.