You "should" polish your finish for any LSP, including Zaino, until the finish is as flawless as reasonable. Zaino can be used after any polishing regimen (product) but if the product contains oils just wipedown with isopropyl alcohol or wash with Z7 or Dawn (1 time only usage). This also gives you a chance to evaluate your polishing and remove any fillers that may be masking surface blemishes. Be care!! This can be an eye opening experience. Some products do more filling and hiding than repairing. :hairpull
Follow with a Z6 QD session and apply Zaino sealant. This will be a perfect bonding environment.
Since most polishes create some dusting, I normally at least rinse the vehicle down to remove all polishing residue from the surface and nocks-and-crannies. I use Menzerna IP and Z-PC Fusion the majority of the time so oil removal is not necessary. I just rinse and Z6 QD.
Hope this clears things up. :wavey