First, i'm new to openEMS and i'm very impressed with what you have accomplished.

I have some technical questions:

**1. Multi-Grid:**

- Besides avoiding the problems around r=0, this method has the potential for reducing running times by nesting.

in Your opinion/experience, how substantial can this be for speeding up solution times ?

- Can this strategy be also applied for a rectangular mesh in openEMS or in general ?

**2. simple circular patch:**

I tried to compare the solution if the same problem in rectangular and cylindrical coordinates, so i can learn how to use openEMS.

Rectangular mesh works fine.

When i apply a cylindrical mesh i get S11=0 identically and after going through all the documentation and blog i can't figure out what am i doing wrong.

I would appreciate your feedback on this (attached).

**3. Future**

- Are there more improvements/capabilities planned for the future ?

- Once i get more experience in this, i would like to see how i can help to improve the documentation and make it more accessible.

Many thanks !