[Plugin: WordPress Backup to Dropbox] WordPress Back Up Running for over a day

I was so happy to find a plugin that would backup my files just how I needed. This is a classifieds site, so it is pretty large. I understand that it may take a bit to back up. So far so good, I have been able to back up a total of 21154 files, with few errors:

(Backup warning on 2012-08-26 at 17:32:27: There was an error uploading ‘/home/content/53/7837953/html/wp-content/uploads/2011/07/495461-50×50.jpg’ to Dropbox
Backup warning on 2012-08-26 at 17:31:49: There was an error uploading ‘/home/content/53/7837953/html/wp-content/uploads/2011/07/495461-150×112.jpg’ to Dropbox
Backup warning on 2012-08-26 at 15:37:09: file ‘backwpup_33_2012-08-26_14-31-46.zip’ exceeds 40 percent of your PHP memory limit. The limit must be increased to back up this file.
Backup started on 2012-08-26 at 14:48:48
Backup warning on 2012-08-26 at 14:48:41: Backup stopped by user.
Backup started on 2012-08-26 at 14:43:35)

Here is my question though, now that I am 21154, the backup process seems to go no further than that.. could it be that it is hanging because the file it is backing up is really large?

I am new to WPB2DB and would greatly appreciate any input.
Thank you.

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