Bezier curves in patch meshes?

[Lord Grievous]

Hi, I'm trying something new in blender to enable a type of "UnrealEd 2d shape editor" workflow. I drew the outline of a hallway section with both straight and curved bezier lines in Blender, then extruded this to make it 3D.

 

https://jkhub.org/albums/7Pin3su

 

I worked on the grid where possible (except the vertices of the bezier curve), I set blender's grid size the same as Quake3 and used snap to grid.

 

But when I try to export it as a .map patch mesh and open it in GtkRadiant it's always missing the top faces of the curved bezier. I've tried exporting it both as quads and as tris but it makes no difference.

 

I would really like to get this working because curved patch meshes look better in Quake3 lighting compared to curved brushwork.

 

Can anyone help me with this please, or is it already know that bezier curves don't work in patch meshes?

 

Thanks on advance

 

EDIT: I just tried it again with only straight bezier lines and exported is as a tris patch mesh and now it shows up correctly.