Seen a lot of confusion about Piko's demo lately.
The demo was PRE-RELEASE ONLY. That's why Kii/oon took down content with it- they were somehow worried that having content uploaded pre-release would hurt sales.
If you used a Piko trial bank, they wouldn't issue a takedown, because they have no way of knowing you used a trial. The only reason you can't do this is b/c, like the majority of V2 vocaloids, Piko had no trial version after release.