I have recently filed a WP at BHC and found that the rquirements were quite different than what was given on the website.
The affidavit in support of application or petition is nothing but the same thing re-typed with AFFIDAVIT written at the top and signed with solemn affirmation at the end. No verificaiton clause as in the petition. This needs to be singed on bottom of each page also, and then notorized.
On the other hand, VERIFICATION means the petition itself is verified at the end, that is signed by the petitioner and verified by signature and stamp the officer in the Court especilly appointed for the purpose. If so VERIFIED, separate affidavit may not be requried. For verificaiton by this officer you would have to affix a stamp on the VERIFICATION page (it is Rs 5 for BHC) and show your photo identity.
About uploading the files on the portal, please check the limit of the file size. It didn't work for me with the BHC. In any case, I guesss, you would have to go pesonally to submit ink signed petition copy and also remove objections raised if any.
Best wishes