33
Solved!
I added an id wrong because I'm editing the class moduleadmin.php.
I'm putting in renderabout function, this code:
$GLOBALS['xoopsModuleConfig']['ip_paypal'];
and, in the file xoops_version.php of modules, in particular in the module TDMCreate, the code:
$i++;
$modversion['config'][$i]['name'] = 'id_paypal';
$modversion['config'][$i]['title'] = '_MODULEADMIN_IDPAYPAL';
$modversion['config'][$i]['description'] = '_MODULEADMIN_IDPAYPALDSC';
$modversion['config'][$i]['formtype'] = 'textbox';
$modversion['config'][$i]['valuetype'] = 'text';
$modversion['config'][$i]['default'] = '48FQE52QN2GEU';
