have a look at https://github.com/ahouben/BleDriver.NET
The c interfaces provided with the Bluegiga SDKs (.c, .h files) are not state of the art for driving a BLED112 dongle from a Windows machine.
This is where https://github.com/ahouben/BleDriver.NE ... _bg_api.py
helps to provide you with a comfortable C# binding given a bleapi.xml from the Bluegiga SDK (only tested up to the 1.1.0-55 version shown here though):
if __name__ == '__main__':
Unfortunately it only provides you with a very low level abstraction of the BgApi commands. A "real" application such as the Bluegiga development GUI or an application that you're looking for would provide more sophisticated functionality on top of BleDriver.NET. This still needs some development effort.
It may serve as a starting point for what you are looking for...