was about to say rings could be worn, but it would smoke all the time, well, not so much on boost with load.
i had an engine doing this and the rings were fooked, but so was the turbo too.
try another turbo and see if still smokes, alternatively, block the oil feed to the turbo and remove turbo and manifold and run engine without the turbo fitted.
if it smokes when revving up and down, then it's the engine that's goosed, otherwise it's the turbo.
also take the exhaust housing off the turbo and check for oil down behind the exhaust turbine.

also the compression tests point to knackered rings, mine gets between 150-160 on a 1.8 zvh.