Michael:
Not sure what is going on w/ the locators between 10 and 10.1 -- I am still waiting on an answer from ESRI support. Still haven't spoken to the second tier support person that the first tier person indicated might be calling.
As a test, I created a centerline/street layer shapefile from scratch consisting of 2 intersecting streets and 4 line segment (1-100 and 101-200 N MAIN ST and 1-100 and 101-200 W ELM ST), created a dual range street locator for these segments, and could not find any address that I typed..................
That was with 10.1 -- I have not moved that layer over to 10 yet to try.
I would suggest create your locator in 10 and use it in 10.1 if you need to proceed w/ anything that you are doing.