Complex sentence: Despite its shortcomings and short existence, QUBE occupied a unique place in media history: it was a venture that encouraged entrepreneurial media activities, and so, it provided a unique foundation for a disproportionately large number of media innovators.
Split into simpler sentences: Despite its shortcomings and short existence, QUBE occupied a unique place in media history. Having been a venture that encouraged entrepreneurial media activities, it provided a unique foundation for a disproportionately large number of media innovators.