If you are an existing BQE customer using BillQuick desktop, you can have your existing data moved to our new cloud-based application, CORE. The entire data migration process is handled by our Data Migration Team at a nominal charge. You can contact your Account Manager at firstname.lastname@example.org for this. Check out this article for details: Data Migration.
You can check out the detailed table-level and field-level data mappings between your existing BillQuick database and the new CORE database in the attached spreadsheet.