I tried keeping the file in the intended location but even after that, I used to get an error at a later step. After looking at the error log, I found that there was an issue in the downloaded Disk 5 zip file.
I had to rename a folder under bishiphome from 11.1.1.5 to 11.1.1.6. The installation was smooth after I renamed the folder.
I am 99.9 percent sure that I downloaded the 11.1.1.6 zip file.