I've made a small change to the script that will clear all previous selection and then proceed to look for only compound curves:

moi.geometryDatabase.deselectAll(); var crvs = moi.geometryDatabase.getObjects().getCurves(); for ( var i = 0; i < crvs.length; ++i ) { var crv = crvs.item(i); if ( crv.getSubObjects().length> 1 ) crv.selected = true; }

This is actually a good idea, since it will avoid mistaken identification.

Confusion may also arise after having used the "Rebuild" function with the "Refit" option. In this mode only curviture continuous stretches of a compound curve are rebuilt into a single entity; this results in the possibility of a compound curve even after a "rebuild". To avoid this use the "# points" option("keep corners" turned off); since this mode is not adaptive you will need many points - by running the rebuild function a second time, with the "Refit" option, this problem can be avoided.

If your asking why "previous joined lines" are selected: this is the purpose of the script :) - the idea is to select these charlatans :) and 'rebuild' them, this way avoiding spikes/kinks while editing.