Procedure of registering marriage in India (West Bengal) with a Nepali citizen.

My question is regarding the actual procedure of registering a marriage with a Nepali citizen because my wife is a citizen of Nepal and I am a citizen of India by birth. We got married on 23rd September 2017 as per social customs in Kathmandu. Since then, she has been staying with me here in India. Its been more than two years but really having a hard time to register our marriage here. No one has been able to guide us through the exact procedure for the same. We also enquired with the Nepal Embassy in New Delhi and we were told that they would issue a letter to us in order to register our marriage in India and for that several documents were to be submitted to the Nepal Embassy. Thus, we followed every step they told in order to obtain that letter and finally got one. Now, that we have the No Objection letter with us issued by the Nepal Embassy, still facing issues due to my wife not having any address proofs (neither present nor permanent) from here (India) and which seems mandatory during the online application process. I being an Indian citizen have all the necessary documents required for registration. We also tried to apply for the same (offline) in person, but there seems no option. Everyone is supposed to apply online only as I got to know through many sources. This has really been very much frustrating for us. How could a person from Nepal or any other country submit proofs of their Indian addresses whilst they do not hold one? And when they try to apply for documents bearing their address proofs, they are asked for a marriage certificate in order to prove that they are legally married. OMG, what a system is that? Anyone, please please please help.