Download the entire history is great and all but doing so is time consuming for some channels with a stupid ammount of images or many channels in sequence. I suggest the program record the time that the last downloaded image was posted and upon the next instance of the downloader being ran it checks the recorded timestamp and acts like history but from that point onward.
TL;DR:
Save timestamp when downloading stuff, if it breaks or something then it can continue rather than attempting to download everything again being required.
Download the entire history is great and all but doing so is time consuming for some channels with a stupid ammount of images or many channels in sequence. I suggest the program record the time that the last downloaded image was posted and upon the next instance of the downloader being ran it checks the recorded timestamp and acts like history but from that point onward.
TL;DR: Save timestamp when downloading stuff, if it breaks or something then it can continue rather than attempting to download everything again being required.