sudo zypper install wine
Then choose OSS Driver (not ALSA Driver) in the Audio tab. Follow the other steps, i.e. closing it, run winecfg again, choose the right settings for DirectSound.
After that, download Spotify for Windows. Open Dolphin, find the download file, click on it. Wine will be automatically launched and the installation will start. After a while, you can enjoy Spotify (even with systray integration).