Sorry for the delay in coming back to you. I’ve been in touch with my colleagues in Hamburg trying to find out whether we have a good source of truth for what the actual mapping is for the Latin Percussion kit. We don’t have a default percussion map for that patch because we don’t have a list of which sound is produced by which MIDI note, and it doesn’t appear that such a list actually exists anywhere within Steinberg; the various drum kits in the HALion Sonic SE content are licensed from Yamaha, and it appears that the original mappings for those kits are somewhat lost to the mists of time.
So I’m afraid you will have to create your own percussion map if you want to use the Latin Percussion kit. The basic job is to open the HSSE3 window and note down the sound produced by each key. HALion Sonic SE 3 uses the convention that middle C, MIDI note 60, is known as C3. The lowest mapped note in the Latin Percussion kit is note 24 (C0), and the highest note is note 96 (C6). My sense is that most of the notes produce the same sounds as the existing Yamaha XG kit, with only the notes in the top two octaves including a significant number of different sounds.
You could therefore start in Play > Percussion Maps by basinc a new percussion map on the existing Yamaha XG map, then modify the instruments and playing techniques between notes 72 and notes 96.
Once you’ve got a workable percussion map, you can create your own percussion kit using the Latin instruments you’ve mapped in the percussion map, and the final step to hook them up together is to ensure that you assign your new Latin Percussion percussion map in the Endpoint Setup dialog.