That's what I've been doing to no avail. So now I decided to start working my way up from the stable version I originally downloaded from wazapp.im, check that it at least works as much as it did this morning and then go on one update at a time. And guess what happens: even the old version has the same problem of opening the loading screen but never actually finishing the job of opening itself. Reboot didn't bring any help, but still I decided to proceed to the next version (28082012). After rebooting it seems that most of the problems got fixed. The group chat is still a bit iffy, since this version doesn't support push names yet (I mean it works, but I really don't remember my friends phone numbers by heart). I reckon I'll take a risk and install the latest on top of this and hope for the best.