Treaty of Sugauli was signed on March 4th, 1816, and Nepal lost places like Sikkim, Kumaon, Garhwal, Simla, Mussoorie, Almora, Ranikhet, Landor, Nainital to British India.

My questions are:

1. Who signed the treaty?

2. Who has its original copy?

3. How is it related to the current political activities with India

4. What is its status in the eyes of International Law?

Can somebody educate me on the Treaty of Sugauli with the back up of citable soureces, please?