Currently there is no chance to change the ownership for Business Processes in Hub/ALM/Interact.
After Creating new Business Processes in BPH/Iv4.5 and importing Interact forms (from previous BPH/I version) as admin user I tried to change the owner of the Business Processes to something more suitable for business. Unexpectedly there is no chance to do that. I'm able to add members to the process, but the owner is not changeable.
I already reported this issue to the BPL support.
[#191677] No chance to change the owner of a Business Process in BPH/Iv4.5 : Global Customer Support (blueprism.com)