Modify an existing .NET C# desktop app

Hi all.
Need someone with good (and demonstrable) skills developing desktop apps with C# under .NET framework.

I've a working desktop app (developed with C#, with ChromeDriver and Selenium), which is running very good, but need to introduce some modifications/features.

After chose few candidates, I'll ask to add an easy feature to the app and I'll know if you:
- Understand the current source code and are able to explain me what the app is doing.
- Send me an image of the app GUI.
- Know how to lead with it and add an easy feature (I'll pay for this simple feature $15 and probably will lead you to get the entire project).

If you bypass that simple (for skilled developers) "exam", I'll discuss with you, the entire set of modifications/features and why not, keep you in mind to give support for the app.

Speak/understand Spanish language, is a good plus.

Please, apply to this project, starting your bid with the word "Entiendo Español" and describing your skills, experience and projects done on C#.

Thanks and good luck.