I am not sure where i am suppost to post this, but when i went through the book(Silverstripe the complete guide to CMS development) i ran into an error. The return function: public function dataObj() in ComplexTableField.php has a error.
ClassInfo::baseDataClass(Object::getCustomClass($this->ctf->sourceClass())), $tis->itemID);
Which should be $this, though i also read this is a deprecated function so i am not sure how important it is.