I have expansions I bought a few years ago, when I used my good old novation twitch with Serato. My twitch works fine, on an old laptop with an old version of the software, and the expansions work fine.
It seems non sense that I need to pay for a DJ PRO license to use those expansions if I am using my SP404MK2 to connect to Serato.
The SP costed me like $500, so its hard to believe roland/serato wont include a DJ Pro license on it, but its more painful to know I can not use my expansions of this new device behind a paywall.