I have LibO 5.0.3.2 and have a XML file that I would like to open. I am new to libo/linux, so any help would be great. thanks to all who do in advance.
An XML file is a text file and Writer should be able to open it. Have you tried that?
Other applications that may be more helpful are text editors such as gedit, Geany, Kate, or XLM Copy Editor. There are plenty of others too.
You might find BaseX (XLM database) interesting too. (sudo apt-get install basex)
Here is a link that has further discussion.