Finally got it!

Nice kata, I've learned a lot with it.

I apologize if I misunderstood, my english isn't quite so good, but I believe that this part of the description might be misleading, ambiguous, or at least hard to understand:

the CodeWars logo is always in the middle horizontally and in the half-1 line vertically;

I say this because the CodeWars logo actually isn't always in the middle horizontally.
I took some time to figure out that, when 'n' was odd (of course), I had to actually put it always in the first horizontal half for achieving the right solution.

Take a look at your examples, specially at the one with (25,30). CodeWars is 8 characters away from the left border, and 9 characters away from the right border. Counting the 8 characters from CodeWars, we have 8 + 8 + 9 = 25. This isn't middle, this is first half.

Although this, I enjoyed a lot your kata, keep up the good work. :)

Amazing!

Interesting and actually a very useful script as well.