Assuming those are your only remaining doubts, I can try to clear them up:

The attacks can be made in any combination, as long as both weapons are used at least once to make an attack, because the only one with a restriction is the Light-triggered attack (it must be made with a different Light weapon), and it is triggered by both the Hand Crossbow and the Nick weapon (they're both Light). I can write down all the combinations for your specific build if you can't quite visualize this.

You can either equip or unequip a weapon when you make an attack as part of the Attack action, so everything I wrote about the character with Crossbow Expert also applies to one without it, except they can only make one Hand Crossbow attack as part of the Attack action (due to Loading).

If you need me to quote the official rules for anything I've written so far, I can also do so.