Welcom to Sabayon, especially SL with KDE. I'm a KDE user also.
You can make an easy check.
Boot from Live CD or memory stick.
When KDE DE appears, right click on Wireless tray symbol and you should see the routers in your environment.
Then find your router's (your network) name and right click on it.
After that you will be asked for adding a network connection and inserting the password from your router.
Then (this happens ever at first time when you use an application which needs a password) another window with the KDE wallet manager will open. You will be ask for a password for this the KDE wallet manager.
The (standard) KDE wallet keeps all your passwords for applications, e.g. Chromium, network passwords...). And the wallet manager provides, that every time, the applications needs the password, that password is given from this wallet manager (so you don't need to enter again).
So, at first call, the KDE wallet manager needs a password itself.
Then I choose basic configuration wit NO password (I let it empty), then I confirm and in future KDE wallet is opened without asking me for itself passord.
But then it will keep also the wireless password (you should wait a moment).
And you should answer the question 'Give access one time only or always or deny...) when the wallet manager asks you.
I say 'Always give permission'.
I do the same way after installing on disk. Because I don't gave a wallet manager password (empty),
after reboot, the wallet manager gives the network password to network manager and I get connected.
Hope to help you.
-Linuxfluesterer (I love KDE ...)
TTIP is NOT YET stopped. Especially consider NHS and ISDS topics. Talk to your local politician to open eyes for danger to democracy because of TTIP