Hello,
I wasn't aware of a hard 30 minute limit on our end for an open
connection, but it's of course possible. I'm assuming that you can't
do anything to improve your Internet connection speed and download
things faster. If you're not already doing so, have you tried
retrieving the gzip-ed version of the report XML instead of the
uncompressed version? The .zip-ed version would obviously be much
smaller. You can get the URL for the gzip-ed version via the
getGzipReportDownloadUrl() method instead of using teh
getReportDownloadUrl() method:
http://www.google.com/apis/adwords/developer/ReportService.html#getGzipReportDownloadUrl
Cheers,
-Jeff Posnick, AdWords API Team