Standalone Skype Application modification + Source available

Hello! I have Skype application made by another freelancer. Unfortunately that freelancer is not available for next few weeks due to his personal issues. i have source codes and i need you to modify the same skype software. It's a standalone skype, We don't need the orignal skype to run this. I made this application with limited features ( the features that i need only. ) Why i made this application? : I made it to hide contact numbers and skype user names from my employees, My employees use this software in my office. They only can call and share screen with my clients for E-Learning purpose. This application has left contacts area. message receiving area, message sending area, call, disconnect call, share screen option only. And that's all what i need. What modifications i need in this?: 1: I need you to make a beautiful GUI for this software. Current GUI is bad. 2: Contacts Online/Offline status is not updated correctly/automatically . fix it and show online/offline status in real time. 3: Display small popup in right corner of screen when someone comes online in skype. 4: Remove the Message sending/receiving area from this app. ( so my employee can't see messages and can't send messages to my clients ). 5: make screen sharing STOP option and button. 6: Display error messages ( which we see in skype for bad internet connection ) in this app. 7: Make Speaker, Mic selecting option in this app. currently it uses default mic and speakers. 8: don't load contact list with user name. make a stick option to not load any contact in left area until got DISPLAY NAMES from skype server. i want to show display names only. not the user names of my clients to my employees. I will upload full milestone and that will only be released once got the application and tested that there is no bug, virus, adware etc. I can send the app in PM if needed including source codes.