Hi,
can someone help me understand the Creation Kit nomenclature better? Especially the nomenclature for the solitude architecture assets.

Let's break down a piece and see what it means, this same setup can be applied to nearly all kitpieces in the CK.

For example, NorRmSmCorIn01:

Nor - Nordic, the tileset it belongs to.

Rm - Room, the type it is. Frequently things like Room (Rm), Hall (Hall), Platform (Plat), etc.

Sm - Small, the modifier. This is the varient of rooms that are 'small'. Nordic also has the large rooms with very high ceilings. Most tilesets have a Sm and Lg (Large) variant to them. For both halls and rooms. Note, sometimes Lg (Large) is instead (mistakenly?) called Big (Bg).

CorIn - Corner turning Inward, the kind of piece it is. This is an inward corner. There are also outward corners (Cor), walls (Wall), middle pieces (Mid), etc.

01 - Varient 01, some pieces have multiple varieties of minor shape adjustments. Many do not, this is most frequently applied to wall pieces, hallway pieces, and mid pieces.

The Solitude pieces are probably without a doubt the hardest kit to understand. It is the most complex kit and it has the most pieces, also allowing for the most specific construction. I recommend you look at what I wrote above, understand the basics (Look at the cave pieces, imp pieces, etc. Understand their names) then look at a vanilla Solitude cell and try to crack the code. I did it long ago but it was messy and slow. Hopefully this helps push you in the right direction!

It's all explained in one of the first tutorials on the Creation Kit web-site: http://www.creationkit.com/Bethesda_Tutorial_Layout_Part_1#Kit_Naming_Conventions