May we’ll have been picked up by other articles etc but played this last week at Dragonmeet so can shed some light here.
The symbols (such as the Oblivion Gate, Crossed Swords, and Dragonborn Helmet) can be spent to trigger extra abilities on the roll (such as damage that can’t be blocked etc)
Defence is done using the same colour die as the armour you’re wearing - light armour uses the yellow dice, for example. I found it much easier to get my head around than Fallout.
Dice order is Black being the best, red is average, yellow not so good. Green is accuracy dice. White is the skill dice.
The potion bottle didn’t come up in our game, and I think replenishes Stamina or Magicka but could well be wrong there.