[dhula]

Are the readings dry or wet?
If dry then do a wet test and see what they look like. If they go up then you can surmise that rings/cylinder boar wear is likely the cause of the blue smoke. If they don't go up then it's something else.

Did a bit of searching aruond and couldn't find anything concrete but the 2.5 has a compression ratio of about 21:1 according to the service manuals so by my quick and dirty calculations (CR X atmo air pressure) your compression pressures should be somewhere near 310psi as a minimum reading
The book says no more than 5bar/72psi difference between cylinders.

As an example, another deso engine in the family has a 17:1 compression ratio and the minimum pressure reading for that engine according to the book is 250psi