.utm files are, in general, a list of items that can be bought by the player, along with allowing the player to sell items as well, functioning as a store. Viewed in KotOR Tool, there are two tabs, those being a Basic and a Comments tab. Unlike other ut* files, this type does not have a specific name attached to it, since the store interface is always launched through a dialouge option, and thus a script - at least for the stores in the vanilla games.
ResRef - A string of text that matches the utm file's name.
Tag - A string of text that matches the ResRef.
Buy/Sell Flag - Defines if a merchant will buy and sell items, only buy items, or only sell items.
Mark Up -
Mark Down -
OnOpenStore Script -
As with most UT* files, the comments tab is not widely used.
The inventory button, as viewed in KotOR Tool, is essentially a list of items that is on offer by the shop. However, like utp files, some items can be loaded into this inventory through a script, and will not appear in this list, but the item(s) will appear in game.