A problem with customizing RSS feed

I met the following problem with customizing RSS feed:
My WP theme allows to set up an additional blog but doesn’t says a bit about its RSS.
The additional blog is a blank page that uses a theme template that calls posts written under a theme-predefined type (for example, “news”).

To set up a separate feed for this page, I downloaded a WCM Page Feeder plugin that allows to feed a single page, but the page appears blank because it is really blank and just calls a template with content. Also, I tried solutions with setting theme custom page template but got the same result: the custom feed works, but shows blank page. And vice versa, I cannot include these custom-typed posts to overall site feed because of such page structure.

I’d appreciate any ideas and solutions. Thanks in advance.