microstripes 7.5

Hi! I need help in modelling a coaxial input and output port for a combline filter. Im using microstripes 7.5. I have done the tutorial for the patch antenna several times but i cant get the same principles to work with combline filters.

Please help!

Instead of making a rectangular ground and then making a port ..just try to create a holllow cylinder filled with dielectric and center conductor ....and try to define the port in the inner radius of the cylinder. or upload the model for have a look.