Thanks to all for the answers!
One final question: the NAV website offers several downloads. I just want a wallet to keep my NAV in. Will the thin client do this?
Yes for sure, the thin client is a very easy wallet to hold your Nav Coin. You could also keep it in a mobile wallet. As you like

I Like Nav coin just the way iT works is way to hard are the devs around on this forum ?
Can you tell me if your looking to make the full node wallet easier.
And the navtech aswell people dont wanna delete a full appdata folder
And make a config file.
Also people want a easy anon send without adding servers.
Just My opinion why this coin is not getting more attention atm
For now the thin clients provide an easy way for holding coins. Staking is a little more complicated but by no means impossible with the available guides. I do understand however that for the average user it is too complicated. Unfortunately the team is limited in time and can only do so much at the same time. Offering an easier way of staking, anon sending and usage of Nav Coin in general always has a high priority. But next to that innovations like Navtech Polymorph also take up resources.
Now the focus is on the sync fix for 3.9 and the projects as mentioned at NAVcoin.org/projects. Hopefully soon we will see easier options for anon transactions and staking coins. Keep in mind that the webwallet will come soon!