I suggest creating a version of this Kata but asking for performance so you need to use mathematical operations to iterate the number instead of using substrings.

The Side property is not found neither the OutputBoard method. Can you update the description?

The translation is not good. The name of the class is not the same in the unit tests. There are no MorseCode dictionary with de morse values (Or I can't finde the correct name).

The test in C# haves, in AreEqual, the expected and actual collection swapped. The first is the expected in the test and the second what the method gives. This can be so anoying.

https://msdn.microsoft.com/en-us/library/ms243763.aspx