Step by step:
Drop Footage in comp1
Select Footage Layer on timeline – Right-Click: Pre-Compose , you now have FootageComp2
Double click to enter FootageComp2
Apply Twixtor (100% speed)to the layer
Go back to Comp1, select FootageComp2 layer : right click ( time | Enable Time Remapping)
Set Time Remapping
Voila!
Pierre