Hi Carlos,
within display_template you can only use the syntax allowed on an .adp page.
You can solve the problem executing the onedraft::mydraft::get proc within the db_multirow and assigning the result to a variable (remember to extend the multirow with the variable name).
Finally you can rewrite the clause as:
display_template {
<img src="/resources/prueba/cross.jpeg" width="16" height="16" border="0">@multirowname.variablename@
}