If you want to choose a build duration using a short rage of times, between 5 frames and 3 seconds for example, you can set your mandatory build in time to 3 seconds. Then make your build-in animation work with behaviours that have an End Offset parameter (such as Ramp and Oscillate).
You can use Ramp behaviours to modify Opacity, Gaussian Blur amounts as well as Position layer parameters.
Set the duration of the behaviours to 3 seconds. Add their End Offset parameters to a rig so that End Offsets of 0 map to a build-in time of 3 seconds, and a higher number maps to a quicker build-in. You can then publish that rig yo FCPX for some build-in duration control.
The main part of the title only needs a single frame before a mandatory build out marker. You can then build out using behaviours and rig their Start Offset parameters.
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Alexandre Gollner,
Editor, Zone 2-North West, London
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