Usage of Class ecm.model.SearchQuery API

Answer

1) You must provide the repository in the parameters.
2) You must include ClassDescription in the select statement, otherwise you get the "API_PROPERTY_NOT_IN_CACHE: The ClassDescription property was not found in the properties collection." exception.
3) You must include the resultsDisplay parameter, otherwise the search will return the properties configured for repository's search results and otherwise ignore the properties in the select statement.

Example code below:
queryParams.query = "SELECT ClassDescription, DocumentTitle, ContentSize, LastModifier, ID, Creator FROM Document ORDER BY LastModifier";    
         queryParams.retrieveAllVersions = false;                       
         queryParams.retrieveLatestVersion = true;                      
         queryParams.repository = Desktop.repositories[0];
         queryParams.resultsDisplay = {
          "sortBy": "LastModifier","sortAsc": true,
         "columns": ["DocumentTitle", "ContentSize","LastModifier", Creator"],
         "honorNameProperty": true};
var searchQuery = new SearchQuery(queryParams);}                                 
         searchQuery.search(function(response){
console.debug("::response", response);                     
             console.debug("::response", response.getColumns());        
             console.debug("::response.items[0].name", response.items[0].name);
}