First, I'm not sure what you mean by v04.05.05 not supporting the News Feed (RSS) module.  Can you give some specifics, as I've used the News Feed (RSS) modules since the early days, and there is no version that I am aware that does not support it.  Which version of the News Feed (RSS) module are you using?

Secondly, you would need to set up the XML/XSL module in similar fashion to the RSS module.  Specify a URL for the news source, and then specify the XSL you want to use for the translation of it. If you don't have a lot of experience with XSL or don't know which one to use, there are plenty of examples on the News forum.  What is available in the default DNN files depends on the version you are using.  Version 3.0.1 has a default XSL that handels most types of RSS feeds in a simple translation, mostly in RSS v0.91 feeds, but will work to present minimal info for RSS v2.0 feeds.

The new RSS module has 3 default XSL's, but that version does not work with v04.05.05.  However, the previous version v03.0.01 still is available and I would recommend using it.  Otherwise, the XML/XSL module will work.  The only difference is that the XML/XSL module has a bit more flexibility to handle not only news feeds but other types of data islands and their translation.  The XML/XSL is what I use for non-standard RSS feeds, or other types of feeds like Atom, RDF, and OPML.  You can use either, but it requires a bit more knowledge with the XML/XSL module to sort out which XSL to use, which really depends on the type of news feed source your are using.

Hope that helps a bit, but if you need more just give an example of the news  source (URL) you are using.