Probem with local rss feed via xml file

Hello all,
I am using Xibo since years in a “legacy” environment with XAMP. Now I am switching to Docker for Windows.
I have a layout with a ticker region that is being served by a local xml-file, that is generated via a VBA makro within an Excel spreadsheet (this is the most easy way for me to have non IT staff updating the content).
The local xml file is saved at \shared\cms\web\userscripts\rss and has the following content:

<?xml version="1.0" encoding="UTF-8"?>
<rss version="2.0" xmlns:content = "http://purl.org/rss/1.0/modules/content/">
<channel>
<title>Xibo</title>
<link>http://localhost:81</link>
<description>Mycompany Mysite Digital Signage</description>
<language>en-us</language>
<item>
  <title>This is the title text</title>
<description>

This is the description text

</description>
</item>
  </channel>
</rss>

It is accessible via browser from all clients and the server as well. I get no errors viewing it with IE, Firefox or Chrome and all browsers are seeing it as an rss feed.
It also works well in my legacy enivoronment with Xibo version 1.8.4. The docker environment is using 1.8.11 and here it is not working. The feed widget appears completely empty and looking at the logs I see this error.
16825 45f4f95 08.10.2018 12:54 WEB GET ERROR /playlist/widget/resource/6/17 Unable to parse feed: XML parsing error

I already found a post related to a similar problem: Xibo CMS 1.8.7 Custom - RSS Ticker Problem, but changing the source is no option for me as well as switching to Linux.
Is there any way to change the xml file so that Xibo is accepting it without a parsing error?

Thank you for including the above information. I modified the formatting of the feed you provided in your post and saved it as rss.xml in the shared/cms/web/userscripts location. In the Feed URL field of my Ticker, I entered the address:

<MY_CMS_URL>/userscripts/rss.xml

After doing so, I was able to set and display the tags listed in your feed. This was using my 1.8.11 Docker install. Below are the formatting changes I made:

<?xml version="1.0" encoding="UTF-8"?>
<rss version="2.0" xmlns:content = "http://purl.org/rss/1.0/modules/content/">

<channel>
	<title>Xibo</title>
	<link>http://localhost:81</link>
	<description>Mycompany Mysite Digital Signage</description>
	<language>en-us</language>
	<item>
	  <title>This is the title text</title>
	  <description>This is the description text</description>
	</item>
</channel>
</rss>

As a test, under the Appearance tab of the Edit Ticker page, I ticked the Override the Template? box and created a simple layout that would display the Title, Description and Link elements from the RSS. They displayed correctly without error. Below is an image showing the result of using the edited version of the RSS you have created:

I would recommend trying the above suggestions to see if the issue is resolved. If you are still receiving errors and no information from the feed is being shown, please let me know.

Many Thanks.

First of all thanks to DanBW for his approach to help me.
The problem is solved now and has nothing to do with the xml file itself.
The issue was based on the virtual network that Docker for Windows is creating. I hope I can explain it without too much errors:
The PC that is hosting Xibo has the normal fixed IP. This get’s resolved normal when I try to access it from any other PC on the network. But when I ping the hostname from the machine itself, it is resolving to another IP adress that comes from the Docker for Windows installation. So the problem is that the ticker file cannot be found as it appears to be hosted on a different IP when using the hostname of the Xibo machine.
My solutions for this was to use the fixed IP of the Xibo computer.