If I install the weekly or month-end data updates from the Web site do I still need to install the monthly update CD
If you are installing the full weekly update or the month-end update, there is no need to install the monthly update CD. Any program changes, such as "bug" fixes, new screens, data fields, etc. are captured when you install either of these two files.
While the partial weekly update also includes program changes, it does not update all of the data in the program. Therefore, if you only make use of the partial weekly updates, it is important that you install the monthly update CD for periodic updates of the data not included in the partial update.