Hi Sryoung,
Thanks for the suggestion. We should be tackling this two-fold in the later versions. Firstly, we will most likely stop the download process on encountering any error. Secondly, we will be providing a gap analysis function that should highlight data gaps similar to the way your program is doing.
For the moment, I would highly recommend the use of the “Download” feature to re-check and re-download missing information where necessary. You can make this feature can go through your entire date range and it will only download information that is missing or corrupted. Of course, you should ensure no errors are generated during the operation as it indicates some problem during the download process. Note also that whenever you attempt an export, the same verification & repair process is applied.
Regards.