Right, I am getting annoyed with 'I can't get ELS V7 to work'.
Follow all these steps, and Make a Back up of ELS V6.1 if this still does not work.
Download the Pack, clearly obviously.
When you have downloaded it, if it is in a WinRAR archive then Export the whole Folder to a seperate location, NOT where your GTAIV is.
Now, you need to open ELS.ini and Scroll down to the bottom.
You will see [ AMBULANCE] and various others.
You MUST Change 'off' to 'on' otherwise it WILL NOT WORK.
Following this, export Everything, including the folders in to your Main GTAIV Directory!
Now, I have noticed the issue of not being able to use the Control Panel in game.
For some people, it works with Alt+M, but for me it didn't. Try Ctrl+M to work the Panel.
If this still does not work. Read this again, do it again. Don't leave anything out.
READ THE DAMN MANUAL