<disclaimer> I'm new to animation. Haven't really done one yet. </disclaimer> I have seen in done in the following two Moho tutorials.
https://www.youtube.com/watch?v=dWdV6suYUhI
and
https://www.youtube.com/watch?v=6t-fGJCmy1A

I assume in can be done similarly in CTA4.

1. Create a door with a rectange shape.
2. Bring to Composer Mode. Adjust the pivot point eg. tick the bottom right-hand box.
3. In Stage Mode, adjust player to frame no. 20
4. Click Prop Key Editor>Deformed>Choose the skew effect. Adjust accordingly.
5. Make sure the pivot point stay at the same location on frame 1 and frame 20.


YouTube Tutorials Here

I like making houses and make the character come and go but it'll look more better if I can animate the door open instead of walking to a new scene. There are some doors that reallusion has but those aren't really that good. Anyone know how to animate a open door on the side and up in front too? It'll help a lot thanks.