Why don't I get traffic information for anything except major highways, is there something wrong with my unit or my service subcription?

No, there is nothing wrong with your unit or service. The current database on which the service operates is limited to major limited access roadways.

While trying to route me around an accident, Why did my navigation unit instruct me to use an exit which was closed for construction?

The traffic database on which the service operates is lilmited to major limited access roadways and does not include on ramps or exits. This data is slated to become available beginning with the fall 2007 map. With that map, on ramp and exit data will only be available in very large metropolitan areas such as New York City and Los Angeles.

Why did my navigation unit with traffic route me onto a service road when the freeway was slowed by an accident. The service road was as slow or slower than the freeway, do I have an incorrect setting?

No, you don't have an incorrect setting. The database that the traffic service operates on is limited to major limited access roadways and has to assume that surface roadways are opn and moving better than the blocked major roadway.