Regarding your second question:

See https://www.vmix.com/hel...ourcesTitleMapping.html:

'Format: This option can be used to add additional text to the data, for example "Name: {0}" will output the data as "Name: Bob"'


First question, probably possible via scripting, if your vMix version allows it, for example:

In GT Title, hide the title field that is mapped to the datasource and add a (visible) static title field.

Then, via scripting:
- Read the content of the hidden and mapped title field.
- If empty, write a '0' to the visible title field, if not write the content of the hidden title field to it.