Hi,
The solution was to upgrade the firmware with Philips Hue App (the official one).
Now, the firmware for this bridge is 1960062030. I have all the 3 leds working.
https://discovery.meethue.com/ is also working, I mean, I can see my bridge.
Hue Essentials (non-Philips app) was able to update all the lights (software version: 1.104.2) and my dimmer switch (software version: 2.45.2_hF4400CA). This Hue Essentials app rocks!
It was NOT an issue with networking, just the out-of-the-box firmware was too old to be able to be configured without the upgrade.
Best regards,
Patrick