ok! works fine.
Changed in
lappend all_candidate_tables2 [list $i:text(checkbox),multiple,optional {} [list options $opts ] [list html {checked checked}]]
Results:
<td> <input type="checkbox" name="table1" value="field1_of_table1" id="lista:elements:table1:field1" checked checked="checked" /> </td>
Many thanks Andrei
