Resuming might be important for potential customers. I came across that here Jet – Automate point to point file transfers | Signiant as potential requirement from large data customers when doing a bit of research for my suggestion here: The digital cinema as potential Tardigrade use case? - #40 by jammerdan
From a general perspective it does not sound too hard to implement a resuming feature as data is up- and downloaded in parts anyway. So if a user has downloaded 40 of 80 parts and the transfer gets interrupted it should be possible to make the software in a way that it downloads only the missing 40 parts (or whatever number is required to successfully create the complete file). Same goes for uploads.
Such a resuming feature could save Tardigrade customers time and bandwidth cost.