Thank you to everyone. Check out the finished product.
https://3dwarehouse.sketchup.com/model.html?id=f044d1ee-6d43-461f-a16d-1f60ce57acd4
You can change the sizes in Component Options. Don't inspect too closely and it looks pretty darn good!
Thanks again!
Hard to really tell what your problem is but:
When you scale a component you don't change it's original instance saved in the model.
That specific component effectivelly displays as scaled but it is actually different from what you see in it's original state.
If you insert it from component browser (wich you seem to have open) it will be inserted at it's original scale.
The same thing might happen in some other situations but what you have to be always sure of, is if your component is at a scaled size or the actual scale.
For being sure of this you can use "reset scale" on the component in the rightclick context menu.
Also you can insert a component at original scale, scale it to a new scale and them make it save that scale as if it was the original scale. You have to use "scale definition" from the rightclick context menu to do this.
What you are probably missing is that you bring a component into the model by locating it in the component window, selecting it, and then placing it in the model. If you just open a file in which you saved a component, it opens as a model.
Thank you for the support. I have a love/hate relationship with this tool, but I'm feeling more love as I learn more. It's opening up quite a few possibilities. Thanks again!
A Dynamic Component might work for your application however you need to keep in mind that resizing is done via scaling. In the case of a component with end or surface details such as my door rail, scaling would also scale the geometry on the end of the rail. The solution is to divide the rail into three separate components. Once for each end and a third for the middle section. Then changing the length of the rail would involve moving one end component and scaling the center section. This works nicely as far as appearance goes but if you also need something like an accurate cut list from the model, dividing the rail into three components creates a problem because the three components get reported not the entire rail.