Querying a Clarizen Project/Task in PHP - php

Question

I'm currently trying to get a list of all Clarizen active projects so that I can modify some properties of its tasks. I've read the Clarizen API but it doesn't have many informations on PHP queries. What I managed to do so far is to query all the projects and then test their status one by one. In practice this is not a good approach since I have thousands of projects and not all of them are listed at once. Here's the code:
//LOGIN PROCCESS
$soapUrl = 'https://api.clarizen.com/v1.0/Clarizen.svc?WSDL';
$soapApiUrl = 'http://clarizen.com/api';
$soapConfig = array('exceptions' => 1);
$request = array();
$params = array(
'userName' => $username,
'password' => $password
);
$client = new SoapClient($soapUrl, $soapConfig);
$response = $client->Login($params);
$sessionId = $response->LoginResult->SessionId;
$userId = $response->LoginResult->UserId;
//Create a SOAP header containing the session ID for future requests
$header = new SoapHeader($soapApiUrl, 'Session', array("ID"=>$sessionId));
$client->__setSoapHeaders($header);
//Create a Query object
$userQuery = new stdClass();
//Set the name of the entity type you are querying
$userQuery->TypeName = 'Project';
//Select the fields you want retrieved from that entity
$userQuery->Fields = array('Name', 'State');
/* Doesnt work...*/
/*
$userQuery->Where = new stdClass();
$userQuery->Where->LeftExpression = new stdClass();
$userQuery->Where->LeftExpression->FieldName = 'State';
$userQuery->Where->Operator = 'Equal';
$userQuery->Where->RightExpression = new stdClass();
$userQuery->Where->RightExpression->Value = new stdClass();
$userQuery->Where->RightExpression->Value->TypeName = 'State';
$userQuery->Where->RightExpression->Value->Value = 'Active';
*/
$request[] = new SoapVar($userQuery, SOAP_ENC_OBJECT, 'EntityQuery', 'http://clarizen.com/api/queries');
//Execute the request
$result = $client->Execute(array("request"=>$request));
3 questions follow:
What is the right way to query in PHP with the "WHERE" clause
How to fetch the tasks of this project and then, for example create a Stopwatch for it.
How to continue the query until the hasMore flag is 0, or is there a way to fetch the entire thing all at once?
Thanks in advance.