How to add ciopfs to etc/fstab?

I have questions about "ciopfs". Lately I found, that "ciopfs" command can help me to deal with case sensitive problems for games and mods. And it worked just fine till I booted today and found, that my mod directory is just empty. I added to etc/fstab it like this:

/mnt/extra/.Data /mnt/extra/Data ciopfs allow_other,default_permissions,use_ino,attr_timeout=0 0 0

But it did not work well. In console it returns error "bash: /mnt/extra/.Data: Is a directory". I found many examples in google, that explained like this. Then why it's not working for me and how can I fix this?