You should not be reflashing the card or anything like that. On your computer go into network settings and choose Airport from the list on the left. This is what I mean when I say wireless adapter, this is your computers wireless adapter, Im not talking about the little dongle you got with the HM. When you have Airport selected in blue on the left your wireless SSID should be displayed to the right. Click the advance button and you will see a screen that looks like this:
Make sure it says Using DHCP like in the picture. But your IP should be 10.0.1.X (X could be any number it doesn't matter) your router will be the same 10.0.1.X (X could be any number it doesn't matter probably a 1). If that looks ok then close the network settings. Now with the usb dongle in the Pi that they sent you plug in the power supply. The power supply and the wifi dongle should be he only two things connected to the HM. Watch the screen to get the IP address. Enter that into your computers browser. That should be it. Based on your previous posts your HM is connecting to your wifi network. If you have all those other devices connected I dont think you have any problem with "isolation mode" because the hue lights have a phone app to control them if im not mistaken and if that works then there is no isolation mode.
Make sure it says Using DHCP like in the picture. But your IP should be 10.0.1.X (X could be any number it doesn't matter) your router will be the same 10.0.1.X (X could be any number it doesn't matter probably a 1). If that looks ok then close the network settings. Now with the usb dongle in the Pi that they sent you plug in the power supply. The power supply and the wifi dongle should be he only two things connected to the HM. Watch the screen to get the IP address. Enter that into your computers browser. That should be it. Based on your previous posts your HM is connecting to your wifi network. If you have all those other devices connected I dont think you have any problem with "isolation mode" because the hue lights have a phone app to control them if im not mistaken and if that works then there is no isolation mode.