What I check with addRow() function you can add multiple empty rows to tabular form in APEX 4.2.
Isn't that so in APEX 4.0?
But check what you have in Page HTML Body Attribute.
I think you should open new discussion to both your new questions.
That way others can more easily contribute and help you.
Please mention all details e.g. APEX version in new discussions.
And of course example in apex.oracle.com is always best way to show problem.