SSIS "XML Source Adapter" can't make XSD location an expression

I am using the "XML Source Adapter" in an SSIS package.

I notice that although you can specify the XML filename as an expression, the XSD appears to have to be a fixed file path.

This is a problem for me since the path for the XSD is different in my development than it will be in production (in production it's on drive E:, which I don't have).

I'd like to have the file location specified in the config file, but since I can't make it an expression how can I do that?

Also, since they don't have Connection Managers I can't switch DelayValidation on.

Thanks.