The default value should be 7, not 0. I just double-checked in the code, because if it was 0, that would be a problem. However, we have heard a few people mentioning this problem -- something might be corrupting the settings.

Thanks for taking the time to find out what was causing the problem. We'll probably add a safeguard so that '1' is the smallest number, or some other option to ensure that multiple downloads can continue even if the purge time is set to 0.

Thanks!