The problem is that kernel 3.19 does not support firmware version 13 that you can get for Ubuntu 14.04.
The easiest way to do offline is to install Ubuntu 15.10.
The adapter should work without any effort.
You can get it working on Ubuntu 14.04, but you will need to upgrade the kernel and the firmware. I can give you directions.
But you will have to download some packages using another computer and then install them to Ubuntu.
Install to Ubuntu 14.04
Download these files:
http://mirrors.kernel.org/ubuntu/pool/main/l/linux-meta-lts-wily/linux-headers-generic-lts-wily_4.2.0.42.34_amd64.deb
http://mirrors.kernel.org/ubuntu/pool/main/l/linux-lts-wily/linux-headers-4.2.0-42-generic_4.2.0-42.49~14.04.1_amd64.deb
http://mirrors.kernel.org/ubuntu/pool/main/l/linux-lts-wily/linux-headers-4.2.0-42_4.2.0-42.49~14.04.1_all.deb
http://mirrors.kernel.org/ubuntu/pool/main/l/linux-meta-lts-wily/linux-generic-lts-wily_4.2.0.42.34_amd64.deb
http://mirrors.kernel.org/ubuntu/pool/main/l/linux-meta-lts-wily/linux-image-generic-lts-wily_4.2.0.42.34_amd64.deb
http://mirrors.kernel.org/ubuntu/pool/main/l/linux-lts-wily/linux-image-4.2.0-42-generic_4.2.0-42.49~14.04.1_amd64.deb
http://mirrors.kernel.org/ubuntu/pool/main/l/linux-lts-wily/linux-image-extra-4.2.0-42-generic_4.2.0-42.49~14.04.1_amd64.deb
http://mirrors.kernel.org/ubuntu/pool/main/l/linux-firmware/linux-firmware_1.127.22_all.deb
Copy the files to your home folder and run in terminal:
sudo dpkg -i linux*.deb
Reboot and test the Wi-Fi.
lspci -knn | grep Net -A2
terminal command.