taking the user directly to start answering

For the purpose described in the issue title, following this discussion, thedut wrote:

Using Rules, I suggest you :

1. automatically create a node answer with the connected user as author,
2. then retrieving the token value,
3. then build the survey url,
4. and then redirecting to this url in order to complete the survey.

Forgive me if my Drupal skills are not entirely up to it. Anyway this is what I found while trying to execute your suggestion:

Concerning suggested step 1:

I end up with this:

Notice: Undefined property: stdClass::$ls_status em ls_answ_insert() (linha 584 de domain.com/public_html/sites/all/modules/limesurvey_sync/ls_answ/ls_answ.module).
Notice: Undefined property: stdClass::$ls_sync em ls_answ_insert() (linha 585 de domain.com/public_html/sites/all/modules/limesurvey_sync/ls_answ/ls_answ.module).
Notice: Undefined property: stdClass::$ls_last_import em ls_answ_insert() (linha 586 de domain.com/public_html/sites/all/modules/limesurvey_sync/ls_answ/ls_answ.module).
Notice: Undefined property: stdClass::$ls_sid em ls_answ_insert() (linha 587 de domain.com/public_html/sites/all/modules/limesurvey_sync/ls_answ/ls_answ.module).
Notice: Undefined property: stdClass::$ls_lang em ls_answ_insert() (linha 588 de domain.com/public_html/sites/all/modules/limesurvey_sync/ls_answ/ls_answ.module).
Notice: Undefined property: stdClass::$ls_aid em ls_answ_insert() (linha 589 de domain.com/public_html/sites/all/modules/limesurvey_sync/ls_answ/ls_answ.module).
Notice: Undefined property: stdClass::$ls_token em ls_answ_insert() (linha 590 de domain.com/public_html/sites/all/modules/limesurvey_sync/ls_answ/ls_answ.module).
PDOException: SQLSTATE[23000]: Integrity constraint violation: 1048 Column 'ls_last_import' cannot be null: INSERT INTO {ls_answ} (vid, nid, ls_status, ls_sync, ls_last_import, ls_sid, ls_lang, ls_aid, ls_token) VALUES (:db_insert_placeholder_0, :db_insert_placeholder_1, :db_insert_placeholder_2, :db_insert_placeholder_3, :db_insert_placeholder_4, :db_insert_placeholder_5, :db_insert_placeholder_6, :db_insert_placeholder_7, :db_insert_placeholder_8); Array ( [:db_insert_placeholder_0] => 1420 [:db_insert_placeholder_1] => 80 [:db_insert_placeholder_2] => [:db_insert_placeholder_3] => [:db_insert_placeholder_4] => [:db_insert_placeholder_5] => [:db_insert_placeholder_6] => [:db_insert_placeholder_7] => [:db_insert_placeholder_8] => ) em ls_answ_insert() (linha 592 de domain.com/public_html/sites/all/modules/limesurvey_sync/ls_answ/ls_answ.module).

While executing this rule:

{ "rules_create_survey" : {
    "LABEL" : "Create Survey",
    "PLUGIN" : "reaction rule",
    "OWNER" : "rules",
    "REQUIRES" : [ "rules", "facebook_rules" ],
    "ON" : { "facebook_rules_registered_through_fbconnect" : [] },
    "DO" : [
      { "entity_create" : {
          "USING" : {
            "type" : "node",
            "param_type" : "inquerito1",
            "param_title" : "[site:current-user]",
            "param_author" : [ "site:current-user" ]
          },
          "PROVIDE" : { "entity_created" : { "inquerito1" : "Inquerito1" } }
        }
      }
    ]
  }
}

I thought that just creating the node entity would populate the fields by default, but I am guessing I need to set each field value individually!?!? I did try adding actions for "Set a data value" after "Create a new entity" in same the Rule but most of the stuff/fields (most notoriously the ones pertaining synchronization) is/are generated by the module upon creation and does/do not seem to be available.

Note 1: Same happens using events "User logged in using Facebook connect.", "After Saving a New User Account", "User has logged in" or even "Content is viewed" by logged in user.

Note 2: I have switched OFF the "The responses title can not be changed" option (the idea being the node to have the unique username has title). Same happens using user:uid.

Concerning suggested step 2:

How? I do not seem to find a way to retrieve the survey token (for a node survey already created, regardless of the above), neither in Rules nor in Views. In the later the description which goes with the following field title does not match:
"LS answers: Survey language
The invitation and answer token on the LimeSurvey site"

The field indeed pertains the title, shows the language not the token.

I was unable to proceed to steps 3 and 4.

Thanks in advance for any assistance.

EDIT from thedut :
The solution to taking the user directly to start answering is :

1. enable the PHP filter core module (/admin/modules)
2. then import (/admin/config/workflow/rules/reaction/import) this rule :

{ "rules_test_redirect_with_user_authentication" : {
    "LABEL" : "test redirect with user authentication",
    "PLUGIN" : "reaction rule",
    "OWNER" : "rules",
    "REQUIRES" : [ "rules", "php" ],
    "ON" : { "user_insert" : [] },
    "DO" : [
      { "variable_add" : {
          "USING" : { "type" : "text", "value" : "inquerito1" },
          "PROVIDE" : { "variable_added" : { "ls_type" : "survey type" } }
        }
      },
      { "variable_add" : {
          "USING" : {
            "type" : "text",
            "value" : "\u003C?php \r\n$form_state = array();\r\nmodule_load_include(\u0027inc\u0027, \u0027node\u0027, \u0027node.pages\u0027);\r\n$node = new stdClass(); \/\/ We create a new node object\r\n$node-\u003Etype = $ls_type;\r\n$form_state[\u0027values\u0027][\u0027node\u0027] = $node;\r\n$form_state[\u0027values\u0027][\u0027name\u0027] = $account-\u003Ename;\r\n$form_state[\u0027values\u0027][\u0027op\u0027] = t(\u0027Save\u0027);\r\ndrupal_form_submit($ls_type . \u0027_node_form\u0027, $form_state, $node);\r\n\/\/ Do not display the success message.\r\ndrupal_get_messages(\u0027status\u0027, TRUE);\r\n\/\/ Retrieve the Nid for the created node answer.\r\n$nid = $form_state[\u0027values\u0027][\u0027nid\u0027];\r\nmodule_load_include(\u0027inc\u0027, \u0027limesurvey_sync\u0027, \u0027ls_api\/limesurvey_sync_api_answ\u0027);\r\n\/\/ return the survey survey page url.\r\nreturn str_replace(\u0027 \u0027, \u0027%20\u0027, limesurvey_sync_answ_surveyurl(node_load($form_state[\u0027values\u0027][\u0027nid\u0027])));\r\n?\u003E"
          },
          "PROVIDE" : { "variable_added" : { "ls_answer_url" : "Survey answer URL" } }
        }
      },
      { "redirect" : { "url" : "[ls-answer-url:value]" } }
    ]
  }
}

Then change the event to fit what you want to do.
You may need to edit the rule, replacing "$account" by "$user" depending on the event parameter.