Hello;
On the tax id field, you can remove any fields by inserting known info and replacing tag with a hidden field like
Change;
<input type="text" id="tax_id" class="required" name="tax_id" alt="Tax Id Number" title="Tax Id Number" size="35" value=""/>
To;
<input type="hidden" name="tax_id" value="000000000"/>By inserting known values you should not receive a database error.
There may be many solutions to listing stats, one would be to do a sql querie on table ox_data_summary_ad_hourly or ox_data_intermediate_ad and list by date and zone id.
This will allow for marketing stats for specific zones and days,
and could be shown on the page you listed.
Hope that helps, let me know.
Mike