Enforcement Grid on Object

I am trying to apply an enfrocement grid on an object in grasshopper.
In School we have a workshop about 3d printing. So i started to optimize an air guide at home. My goal is to have an wallthickness of about 0.5mm on the whole geometry. To make the geometry stiffer and safe Material and printing time all at once, i would like to apply an enforcement grid on my geometry.
I made a copy of the object in solidworks and exported it as a step.
Then opened it in rhino. In grasshopper i created a little workflow to apply it on the outer shell.
The result looks good on first look, but looking closer at it i can see many problems:

Overhanging x:

The x pattern is overlapping the original contour. How to prevent this?

Crossing of two surfaces:

As i had to split the brep i only have single surfaces which do not interact anymore when applying the grid. Are there ways to prevent this?

Is there someone who can help me please?
Is there a way that i dont have to split the step file up in single surfaces so that the grid can be applied on the whole part as one closed geometry?

I am glad about every hint!

Rippenmuster.ghx (643.8 KB)
Luftführung mit Rippenverstärkung.3dm (1.1 MB)