Limecraft accepts any file format you might come across during your production, including video, audio, stills and image sequences. Also a number of structured master formats are supported, including IMF, DCP and iTunes.
All simple file formats can be dragged and dropped into the Flow library. Some more complex file formats, including image sequences and structured formats, need pre-processing before they can be properly displayed. Hence they can only be ingested using Edge.
You can find the list of supported file formats here.