Problem description: 
If you have data ranges that don't have captions as first rows/columns, and you manually enter a name for a data range as "somename" (with quotes) in the "Range for name" field, then it shows correctly on the graph and causes no errors on save.  When you reload the file, the name is gone, and it returns to "column M" or similar.

Also described here: http://ask.libreoffice.org/en/question/19997/possible-to-set-charts-data-series-name-to-constant/

A workaround is to put the desired constant text in _any_ cell, and pick that cell as the "data range for name"

Steps to reproduce:
1. Create a graph with (multiple?) data ranges
2. edit the "name" property of a data range, in the "name for data range" field
3. enter a fixed string, such as "my range name"
4. ok, verify that chosen text shows on graph.
5. save document
6. close calc
7. open calc
8. open file saved in 5.
9. see that name for range entered in 3 is missing.

Current behavior:
the custom range name is missing when you re-open the file.

Expected behavior:
the custom range name is saved like anything else.
              
Operating System: Fedora
Version: 4.1.6.2 release