DR1-Foundation is the first large release of Euclid data by the SGS in a sequence ultimately gearing up towards DR3 in the early 2030s. The data processing is not yet fully mature, and many of the processing functions have identified pathways towards improvements, some that will be implemented for DR2 and some whose development will be longer and appear in subsequent data releases. We take the opportunity to remind the users of DR1-Foundation data of a few important caveats to keep in mind when working with the data.