You can select whatever tracks you wish, and then export those tracks, and the things connected to those tracks (fx plugins and settings, synth rack plugins and settings, buses) will be saved in the track template.
So, you can create multiple track templates from a single project, if you wish, by selecting one group of tracks and exporting as a track template, then selecting a different group (could be one) of tracks and exporting that group as a different track template, etc.
This is an INCREDIBLY cool feature of Sonar, as you get to reuse what could be quite complicated setups, that could include track folders and all the tracks within those folders, as well as all the settings and if present any contents, along with associated buses and any associated synths and effects.
Then you can insert one or more track templates into a different project, and all of that saved stuff gets loaded into that project, all ready to go. I do this all the time with Battery 3 custom drum kits that have separate outputs for each cell, and separate audio tracks for each of those cell outputs, along with a midi track for recording drum data. All of that gets loaded with just a few mouse clicks to load the track template.
Hope that better explains it. Bob Bone