Ubuntu :: Set Environment Variable In A Launcher?

I am trying to create a launcher which runs virtual box from a custom config directory. For this I have to set an environment variable first then call VirtualBox command. From terminal it looks like:

Code:
helena@mint ~ $ export VBOX_USER_HOME=/mnt/shared/VirtualBox/
helena@mint ~ $ nohup VirtualBox > /dev/null 2> /dev/null &

If I have to create a shortcut for this, I am not sure how to define variable & call the command in a single command. There are some examples on:

[URL]

Code:
"DISPLAY=:0 xterm"

but when I try this, it wont work. My test.Desktop entry (I have started x on :1):

Code:
[Desktop Entry]
Encoding=UTF-8
Version=1.0

pCode]....