To answer the easy question. Rotmeth as taken from the wiki. Rotmeth is a Bosmeri spiced alcohol made from rancid, fermented meat juices. So it basically meat wine. All the wiki has for the background is this copy and pasted from the wiki.
This steaming brown liquid is drunk from a mug and could be mistaken for tea, if not for the Meat Mandate, which prohibits anything made from leaves in Valenwood. Rotmeth tastes gamy, bitter and sugared, and very salty. The effects of Rotmeth include a tingling sensation throughout the body, sounds becoming oddly disjointed, surges of rage which quickly subside, and bursts of laughter. Several hours after consumption the drinker will feel half-asleep, unable to open their eyes fully, and the events of several hours before seem like obscure childhood memories. Rotmeth may seem disagreeable to the palate at first, although the drinker will soon find themself pouring many more mugs.
To me most of that effects sound like flavor text. pun not intended. Now on to the other things you asked about. Its more of a Role play to make ice boulders. I always thought it would be fun to send Dwarfs clad in ice enchanted armor and weapons against the circus.
It would just be reactions to use an iron, silver and steel into there icy version and will need bucket of water for glass and gem. I am gonna look around the wiki and try to figure some stuff out. It not to hard to copy and edit raws. thats not the problem. I made cat blood super high temps and testing that in the object arena. Cats vs gobo no one won, lol. I will be making the weapons out of them a bit worst at cutting but better at piercing and bashing.
Also thank you for the replay