TT Deluxe on Mac displays / prints decimal point for all numeric entries in the federal return ( e.g. 1523. and 0. ) - is this a problem?

Nope. This is not a problem.  This is working as expected. When you enter in the amounts from your tax documents it will round up or round down. For example if your 100-9 states $5,456.63 it would be entered in as $5,467.