Smooth transition at hole trough solid object

Hi there,

my goal is to write a definition with the following procedure:

1. The precondition is a 'wall' with front and backside as free-form surfaces.

2. The wall is subdivided in rectangular elements with defined dimensions.

3. The faces of adjacent elements are converted into single curved surfaces.

4. One or several openings are punched trough the wall which should form a smooth transition from one side of the wall to the other.

The crucial question is how to solve the last part. Since I did not really step into the world of meshes, this will probably the path to follow?! Any help on how I could possibly achieve this - even links to basic knowledge on meshes which I would then study first - is highly appreciated!

I am sorry about the messy definition, this is the first and rough approach for my intention.

Thanks! Rafael