Rule 1: be patient. My problem is solved.
About 20 hours after I lauched the installation of 1.7, my device restarted on its own. The notification for “finishing update…” is no longer present. So it was a long process.
The App Lounge is fully functionnal.
Moreover, my banking apps which were half disabled for the alleged reason of “routed phone” are now functionnal.
Once again, thank you for this great OS.