There is a potential issue with the component View -> Navigator IF you have imported some chapters from Word. In this case, moving chapters up or down inside Navigator MAY very quickly lead to a crash. 

IF this is the case, follow the following steps:

1) Put the problematic file into a new empty folder A.
2) Rename this problematic file from xxx.odt to xxx.zip.
3) Unzip this file. You will see amongst others a file named "styles.xml". In my case this was 50Kb in size.

Next:

1) Again create a new empty folder B.
2) Create a new empty file and save it in this new folder.
3) Rename this empty file from yyy.odt to yyy.zip
4) Unzip this file. You will see again a "styles.xml" file. In my case it is quite small, only 10Kb.

Then:

1) Overwrite the large "styles.xml" in folder A with the smaller "styles.xml" from folder B.
2) Delete the xxx.zip file
3) Mark all your files in folder A and zip them.
4) rename your xxx.zip back to xxx.odt

The problem has disappeared.

You will however need to recreate a number of personal Styles for your own use.

This method is generally useful when imported Word documents contain a dozens and dozens of automatically created styles such as "conten001" etc. Word often creates loads of new styles without the user even knowing about it.