Can we use eknow Integrator to store and track all transaction documents and approvals?

Yes.  eknow Integrator contains an indexed and searchable document repository.  Like all other parts of Integrator, you control who has access and what users can do with documents loaded into the system.  Team members can store and access their documents from within the dashboard pages for each task so there is no need to go to an external repository.  Alerts are generated for documents requiring approval and dashboard reports show the status of any documents in the approval workflow.  The system maintains a complete audit trail showing the date, time and user name for every transaction involving a document.