edge finish - ripples and ridges

[JAZZCNC]

The other issue is that the parts were suppose to be 15mm +/- 0.1mm, but are in fact 15.2mm - 15.25mm. Any chance of bringing them down to 15mm, so taking 0.2mm of the top?

If your asking me can I take material off for you then sorry no can't for reason's won't go into here.

But if your just asking if think it's possible then yes they just need skimming over with fly cutter.
To be honest if cut from rolled Alu plate then chances are it's not truly flat so would need both sides skimming and with only 0.2 to play with then would be touch and go if you'd have enough material to cleanly do both sides.

If you mean 0.1-0.2 oversize and can profile shape be machined to dimensions then yes it's possible but very difficult and timely to re-position on machine to such fine tolerance.
It would need 2 or 3 good clear reference points to work off and lot of messing around with positioning into correct place because with only 0.1-0.2mm to work with there's no room for error.!