Simple and Complex

I have added simple collision by adding the sphere simplified collision, but I would like actors to walk on the boat. What do you think the best strategy would be to allow this?

Can simple collision be applied to water and complex collision be applied to the actor without too much trouble?

What are you trying to do exactly?
the type of collision simple vs complex has nothing to do with how objects interact via collision.

Also, complex collision on such a detailed model is expensive. You should really generate custom simple collision meshes instead.

just remember that Convex does not mean you can have holes in it.
look up the FBX pipeline docks for more info on it.

It will likely take several hours to create the simple collision for the model, so make sure that performance is an issue before you start with it. Otherwise, complex can work.

In the first image, the player and water are colliding with the simple collision.
In the second image, you can see that both simple and complex collisions are enabled.

Before going through the trouble of manually creating the collision, I would like to see if “Simple and Complex” will work.
How can I allow the player to pass through the simple collision and “hit” the complex collision instead?

Can’t work that way.
the mesh - skeletal or static - reacts to collision period.
what collision is defined by the asset (if use complex as simple is checked for instance, or if no simple is avaliable).

To do what you want to do:

Firstly note that this is a workaround rather then the proper way (creating custom buoyancy physics or using the ocean community project to float an item on water).

Second, create a BP, include the galeon/boat mesh with the complex collision.
Add in a box collision component. Customize this components collision to collide with the water (or whatever else but not the mesh or itself).

And that should be that.

The boat would collide with the ocean via the sub component you add to it, while that component ignores the collision of players/pawns etc.
So it should work like you want it to in the end.