Hi,
Unfortunately, this funcionality is not supported by default in the current version (will be available in v 6.0). I am sorry for inconvenience.
You could manage this functionality using
custom tree node handler.
Here you could change
NodeAliasPath and
DocumenURLPath of the document to be lowercase. This way the url would be stored in the database in lowercase format.
Best regards,
Ivana Tomanickova