Helicomparator - quite agree with the lack of confusion over which parts of the upper modes are engaged. The main thing to remember with the 135 is that it's only a 3 axis AP (P/R/Y) so modes are mostly controlled by cyclic. Therefore, with ALT engaged, the collective just controls speed; likewise with IAS hold, collective controls height.
As you can only have two modes of the AP engaged at any one time, you just have to think what you're trying to do!