You should compile the dll use static library. That it can work without the redistributable. Or you can use .NET to write it. So that it can built in the launcher.
Say how exactly should be done, the search for friend, request system, accepting system, action system, all of this and more saving locally.Just like any other browser: save it locally.I'm working on password's encryption in the application, but you need to know that the authentication is done by outside. And of course the passwords are encrypted in database.How you intends save your list of friends and associate with you? or your informations?Why is registering even needed? I don't see any function that would need an external party.
And also there's new features that are coming like this one.Small suggest: Private messages with friends ;)
Still doesn't answer my question why you'd need someone MAC address.
And about the MAC Address is to make the client's session safe.
For those who is getting this error, please download this: Visual C++ Redistributable for Visual Studio 2015 DOWNLOAD x86(32 bit).