Trouble getting NFS to work in 18.06.4

Hello everybody,

I've used OpenWRT for quite some time now with a NAS running through Samba.
Now I would like to migrate to NFS because of a more native Unix solution. I have no Windows machines in my home anyhow.
First of all I already noticed that the current packages for 18.06.4 seem to be broken.
Using nfs-kernel-server from LEDE 17.01 got me the NFS running on OpenWRT 18.06.4.
Now comes the strange part.
Using Fedora 30 I try to mount my NFS share.
This takes quite some time to finish.
When opening the mounted share on my Fedora box it shows it's contents.
Although I'm unable to modify, creatie or read/open anything on it.
Folders appear as "boeken/unknown" files so are not able to be opened.
When creating a new folder/file on the NFS from within the routers, and refreshing the nfs on the Fedora PC this new file/folder will appear in on the client.
This indicates at least that there is some connectiin between the two.
Hopefully somebody can give me some pointers to look at.
I really would like to ditch Samba.

Greetings Jasper