COPS 0.3.4 is out with only bug fixes (First post to download) :
* Hopefully fix metadata update. Beware you should remove the directory php-epub-meta if you have one. Thanks to Mario for his time.
* Fix two warnings. Reported by Goner and Mario.
Only bug fixes, metadata update was finally well tested so most bugs seems squashed !
Thanks a lot to Mario who helped me a lot to understand the sources of the bugs.
I'll push the Synology package soon.
As usual the download link is in the first post.