UPCAT

You have to go to college for verification of documents. Carry original documents and other important things.

Before final submission, there is an option for editing the documents/uploads. If you have submitted finally, then there is no option to edit it. Contact the concerned people and hope they will allow you to re upload.

It will not create any issue. Be relaxed, no need to worry.

I don't think it will create any problem for you in counselling. Tell them the truth, they will manage it if anything happens. No need to worry, as it is not a big problem.

Yes, you will get the benefits of both. EWS and girl's reservation also.

You have to upload the first half of the class 10 marksheet in which your name and date of birth will be there. There is no issue in it as it is not possible to upload the whole marksheet in one document. No need to worry.

Here's the list:
Institute of Engineering and Technology, Lucknow.
Dr APJ Abdul Kalam Technical University, Lucknow.Galgotias University, Greater Noida.
Galgotias College of Engineering and Technology, Greater Noida.
JSS Academy of Technical Education, Noida.
Bundelkhand University, Jhansi.