I've experimented on Caen using the master crescendo as a very rough and incorrect way to add divisions in the French symphonic pattern, but I found master reversibles easier to use for that.
All stages in one group are identical. C-C organs didn't do smooth, one stop at a time crescendos. But you could smooth it out. It's not a correct purist French symphonic approach anyway.
Stages 1 - 5 R full 8' and up and coupled to P GO PD
Stages 6 - 10 P full 8' and up and coupled to GO PD
Stages 11 - 15 GO full 8' and up and coupled to PD
Stages 16 - 20 PD full 16 - 8'
Stages 21 - 25 R P 16'
Stages 26 - 30 GO 16'
Stage 31 PD 32' and up
The problem with that is if you're on fonds 16 8 (4), you don't usually bring in Pedal reeds before manual 16' reeds. So it's just not right, hence reversible toe studs to do it in the right order.
But you could put the 8' series on Cresc A and the 16' series on Cresc B to get closer to the typical order. Of course, these are all just tricks to avoid using the C-C ventils as intended...
A Rotterdam crescendo could be anything you want, since there's no such thing on a neobaroque organ that has to be hand-registered. Having the romantic Swell sort of invites considering a crescendo similar to an American or English eclectic organ, if you want to be crazy.
I've always wondered how the stages were set on some Willis examples.