The transpulmonary pressure is the pressure jump across the alveolar wall (at least, that's what you wrote). The lung itself does not have the ability to expand or contract via elastic stress- that's driven by the diaphragm- so I'm not sure what 'elastic recoil' refers to. Similary, I would call a 'tension pneumothorax' a 'compressiion pneumothorax' because the effect is to keep the lung compressed
Pneumothroax, as I understand, occurs when the pressure jump becomes zero- either the lung is punctured, or there is some other injury that allows air into the pleural cavity. Then, even though the diaphragm is still functional, the lung won't expand or contract since there is a low-resistance alternative flow path for air to follow.
hope this helps...