Connecting Two CPT's with intermediary CPT via CRED Edit Form
You can use CRED hook "cred_save_data" to do any customization you
need and to connect the post using intermediary post entry.
You can find proposed solution, in this case, with the following reply:
This is the technical support forum for Toolset - a suite of plugins for developing WordPress sites without writing PHP.
Everyone can read this forum, but only Toolset clients can post in it. Toolset support works 6 days per week, 19 hours per day.