Thanks for sharing the process. How/ When do you get back the originals from the university?
You don't submit the original documents. They are only for verification purposes and will be returned to you immediately. Mr. Venkatachalam will verify the Xerox copies.
One change: The bank will not have the yellow challan. You will have to go to the Controller of Examination building and from the front desk, collect the challan (account 34). You will then need to submit Rs1500 (yes they revised it - I don't know from when, probably from the new academic year).
Ideally, the sequence of the process for convenience is as below
1. Go straight to COE block and get the challan
2. Go to Admin block and in the academics section ask Mr. Venkatachalam for the university envelope (he may ask to first show him the bank sealed challan, just to be sure you are asking it for genuine reasons). So you could choose to get that done and then ask for the envelope
3. Depending on the sequence of events, if you have the envelope now, go to the post office and paste stamps worth Rs1400 on the back side, and on the front write the WES address.
4. Get 1 set of the xerox evaluated by Mr. Venkatachalam. Give him the requisition letter (a simple one in your language, addressed to the Registrar. Mr V will staple the challan, requisition letter and verified xerox and ask you to submit it at the dispatch section (directly opposite side of the lobby) and the other set he will keep and ask you to leave.
3a. When you are at the bank, ensure you write your mobile number on all 4 foils of the challan. And on the reverse write the currency denomination count.
That is all. Ramesh has mostly given the process, but I'm just sharing my experience (May 2019).