Once you install zotero, you will be prompted to create an account so you can use zotero ANYWHERE on ANY computer.  You DO NOT have to download zotero to use it.  You can go to zotero.org, log into your account, install the browser connector you require, and begin using zotero ANYWHERE.

Click on the graphic below to go to the account creation page.  Please read the document on the zotero ANYWHERE page by clicking on the tab above.