occasionally, I'll download a csv file after the stats were updated and I'll try to upload it and have it graph some of the results, but I just get a blank graph. it seems to be "stuck" like this until the next time the stats update and I get a new file. any idea what could be causing this?
Hmmm, I haven't seen (or heard) of anything like that. On the file you are uploading, are you opening it in any editor beforehand? Google saves the file in a retarded encoding (UTF-16), so the adsense charting tool has to decode it... So it assumes it's UTF-16. If you open it in something else first, it may be converting it to some other format.