I have a set of fields on the Idea object that I need to make read-only upon Save. I am not seeing a direct way to do this in the tool. Does anyone know if this is possible or will it require a custom solution?
You can try creating Process on Idea object that will lock required attributes.
You might use the "Enter Once" option on each attribute. Keep in mind that if someone makes a mistake they can not change the value after the "Save" is done. Correcting the mistake takes a bit more effort.