The Trim Controller page ought to give you an idea regarding how we approach the placement of trim. Overall, what trim gets applied where is not fixed, but depends on the structure as well as preference. How we do this is to take measurements, such as the length along the ridge, and then let you assign what sort of things need to be controlled by this measurement.
For example, if you build a metal roof with a continuous roll vent, the ridge measurement might be used for the roll length as well as well as gasketing for this. Or if you choose a self-sealing venting product that doesn't require a gasket, you might ignore the gasket option entirely. Similarly, a roof using asphalt shingles may use ridge cap instead of vent.
The mechanism for controlling the trim is called a TRIM PACKAGE and this governs what SKU is chosen as a default for what measurement. The package affects all trim in the structure; if you use wainscoting, the trim interfacing the wainscot to the siding will be included so that the type is pre-selected, otherwise it's ignored.
The Trim Package is generally selected by the structure that's being built.
At some point you'll want to color the trim based on your customer's preference, and this is where this menu item is used. Note Step 1. As with packages, you can subdivide the package controlling via a scheme, which is a list of toggle (Yes/No) settings for each type of trim. So if your package is fairly generic for a basic steel sided structure with 1 foot overhangs and a variable (steel or asphalt) roof, you might choose to toggle those items that are specific to the roof. That would mean that you might have a scheme saved as "Metal Roof" and one saved as "Asphalt Roof." What schemes you have will depend on what you normally build and how much variance you have. Note Step 2. This is how you toggle lots of things at the same time.
Note Step 3. If you have toggled a number of items and wish to have the software remember this (you may need this in the future) then you may save the list as your scheme.
Note Step 4. As with the product choice schemes above, you can choose to colorize various areas of a structure and then save these as a scheme. This can come in handy if you are building structures of various sizes and in various locations for a known customer. For example an energy company customer may build storage or equipment sheds as it develops resources in the field, and they want these structures to have a unified look. So the first building you create using company colors is saved as ENERGY_COMPANY_SCHEME. A couple of months later, they contact you again: "We need a new building, a 32x60 shed." No problem; you use the software to create the structure and then apply ENERGY_COMPANY_SCHEME in the trim coloring step. Simple.
The first time you color the trim, you simply choose the color in the dropdown list that corresponds to the group you're wanting to color. <>b>And here's the fun part: the groups are under your control. Where the example here shows "Roof Trim Colors", maybe by that you want to also color match the outside corner trim of the building, or maybe you also coordinate the window and door trim to that coloring scheme. If so, you can set that group up to do exactly that. Although there are 12 groups shown in the example, you may need only 2 or 3 groups depending on what you like to have matched. It's up to you.
Note Step 5. As with product choice, you can save ENERGY_COMPANY_COLORING_SCHEME after you have built the first structure for them. Or maybe you find that there's a lot of call for common coloring choices and you just want to be able to show handsome structures to potential clients on a sales call. How you use this is up to you.