FWIW, the application itself is essentially the same from release to release, with the exception (of course) of new and/or modified tools and functions that may have been introduced. In order to support those changes, the individual datasets may include new, modified or deleted files as well. The first link that Tathagata included above outlines the "delta" PDF included in each dataset that lists all of the changes made from the previous version of that same dataset. The second link from Tathagata is to a general dataset migration Wiki that includes a link to the dataset migration steps specifically for Ss4 to Ss5: Updating/Migrating SS4 Datasets to SS5
Depending on the disciplines you use within ABD, the dataset, and the version you are updating from and to, some (or perhaps many) of the changes may be irrelevant to your workflow and/or customized data. With regards to seed files in particular, again it depends on which dataset you are based on and your (and your IT's) definition of a "seed file". For example, a quick search of the US dataset's Ss4-Ss5 delta PDF returned no results for the word "seed", while the NM delta PDF returned many; e.g., Drawing Seeds, Sheet Seeds, Cell seeds, etc.. So it's best to check the delta PDF for the delivered dataset you've used as a template for your own, and go from there.