Every one of the XPro Styles has been designed to work with the XPro Pak. In other words, the XPro Styles are based on the RealTracks and MIDI tracks content that come with the XPro Pak.

Conversely, the Xtra Styles may require RealTracks and/or MIDI tracks that do not come with the XPro Pak (the XPro Pak is the starter / light version and has limited track content).

If you only have the XPro Pak, then some / many of the Xtra Styles may not work correctly.

Hope this clarifies.

BIAB & RB2025 Win.(Audiophile), Sonar Platinum, Cakewalk by Bandlab, Izotope Prod.Bundle, Roland RD-1000, Synthogy Ivory, Kontakt, Focusrite 18i20, KetronSD2, NS40M Monitors, Pioneer Active Monitors, AKG K271 Studio H'phones