sir, can I upload cast certificate instead of non-creamy layer certificate in the 'community' coloumn in the application of KLEE? will there be rejection of the application : in not uploading non-creamy layer certificate being in the community 'OBC' ?

Anand, a Caste certificate is different and a Non creamy layer certificate is different and the purposes of both certificates are different. So you cannot upload Caste Certificate in the place of Non creamy layer certificate. If you do so, unfortunately you might lose out on Non creamy layer benefits. OBC certificate is to claim 27% reservation but by submitting a Non creamy layer certificate you are mentioning that your family annual income is lesser and so you want relevant reservation.