How can I update the Post Title with the value from a Custom Field using Toolset?
You can use Custom PHP Code to get the value from any input on the edit screen and update - using the WordPress API - the post with that value, but this is independent of whether you use Toolset or Not.
You can see here an example of such code:
This is the technical support forum for Toolset - a suite of plugins for developing WordPress sites without writing PHP.
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