If anyone still having problems with android whatsapp, here's quick solutions:
1) For sound problem: Use some filemanager of your choise and put any sound to /sdcard and select it from the settings
2) For contacts missing: delete all your contacts and add them again _when whatsapp installed_. So if you want to use whatsapp, I highly recommend to install it before you add any contacts to your phone.
Oh, there would be a fine solution for this problem: submit proper Sailfish apps to Harbour, not alien Android apps.
unfortunatelly, I know nothing about programming so that's not gonna happen. I offered to help with something else but still no answer of any kind. Although we were all invited to join the tribe and help create something different