Zyxel NAS542 with ownCloud

Hello gents,
im running ownCloud 7.0.15zypkg006 on NAS542, everything went fine and I do use port 5001.
No issue with Dekstop(WIN) or browser, however while running the app on IOS im able to connect/ login, however each time im trying to upload, create, download or anything it shows unsupported URL.

Anyone with same/similar experience?




from what i know ownCloud 7.0.15 is more then two years old. Maybe the recent sync client versions are just not compatible with such outdated versions of ownCloud?

I´m also running ownCloud server ver 7.0.15 on a Zyxel NAS 540. For some reason, Zyxel does not want to upgrade to a newer version.
After the latest upgrade of the app, it does not work at severversion 7. The sync is also not supported in Windows.
Is it possible to upgrade a Zyxel NAS to Ver 9?