Ok, it's a bit more complicated than that.
On a Windows PC for example, you need to go into the network settings and enable an option in your Wi-Fi connection to allow it to connect to hidden networks.
In Android, you need to remove the network and add it manually or the device won't try to connect again.
On iOS you need to go to Other Networks and manually add the network.
I'm not sure about OS X and Linux.
This is not an issue with the Almond+, but rather a limitation with how hidden SSID's work on the client side.
I'll do my best to get this up in the Wiki next week.