Below is a sample to add Rows in an existing table which can be done through a modifier:

<PROJECT JOBJACKET='Project1 Job Jacket' JOBTICKET='Default Job Ticket 1:Project1' PROJECTNAME='test.qxp' VERSION='7.22'>
<LAYOUT POINTSPERINCH='72'>
<ID NAME='Layout 1' UID='1'/>
<SPREAD>
<ID UID='1'/>
<TABLE COLOR='none' COLUMNS='5' MAINTAINGEOMETRY='false' ROWS='3'>
<ID NAME='Box9' UID='9'/>
<ADDCELLS TYPE='ROW' BASEINDEX='1' INSERTCOUNT='3' INSERTPOSITION='AFTER'/>
</TABLE>
</SPREAD>
</LAYOUT>
</PROJECT>

In the same way, you can change the <ADDCELLS TYPE=Column> to add Columns to the table. In addition, you can use DELETECELLS to remove cells Please refer to the file Modifier.dtd, which is located inside the QuarkXPress Server folder for more attributes related to tables.