Using a pdb file that is not in the database

I would like to model a sequence for which there is no structure in the database. I have a pdb file that is likely to be a better model than anything in the database. I would essentially like to include this along with everything in the database. Given that the structure is confidential, I would not like to upload it to the server. I have downloaded the standalone i-tasser and databases, but I cannot see any information on how to either update the database to include the new structure or to run i-tasser with the new pdb file as can be done on the server version.