Setting Pitch Bend in 12 semi-tones or whatever

As in reason, it depends on the instrument you're using. Its just that reason is generally a bit more consistent in how it organises modulation parameters on its instrument interfaces. For example, in the EXS24 you do it in the matrix editor bit (not sure if thats what its actually called but its the section which runs horizontally across the centre of the interface). You set the Source (Src) to Pitch Bend and the destination (Dest) to Pitch and use the slider to define (in cents) the range of the pitch you want the wheel to affect. On the ESM there is a disclosure triangle on the bottom left of the interface which allows you to set the bend ranges.