Problems working with Broadcom 4352 Wireless card

I suggest the far simpler arrangement for /etc/network/interfaces. I also suggest, so that you can ssh and ftp into the server, that you use a static IP address. If 'em1' is your ethernet under the new naming scheme, you are asking both ethernet and wireless to start automatically. I'd change /etc/network/interfaces to:

auto lo
iface lo inet loopback

#auto em1
iface em1 inet dhcp

auto eth0
iface eth0 inet static
address 192.168.1.100
netmask 255.255.255.0
gateway 192.168.1.1
wpa-ssid <your_router>
wpa-psk <your_secret_key>
dns-nameservers 8.8.8.8 192.168.1.1

Of course, pick an address outside the DHCP pool in the router and substitute your details. Get the system to read and use the changes:

sudo ifdown eth0 && sudo ifup eth0

It may take a reboot.

If your cfg80211 warning persists, I suggest we troubleshoot after we get the wireless to connect smoothly.