For one thing this form is incorrect
<record model="ir.action.report" id="report_bolletta">
<field name="name">Bolletta</field>
<field name="model">tributi.bolletta</field>
<field name="report_name">tributi.bolletta</field>
<field name="report">tributi/bolletta.fodt</field>
<field name="single">False<field/>
</record>
KeyError: 'name'
and then I wonder: a not single report needs one only template fodt file and then it will create as many copies as needed ?
Or, rather, the file should contain some machinery to replicate some form for each record ?
Thanks