Momento, presume that you have a chart program within which you have collected price data. What you need to do is convert whatever file format that program uses into AG's format.
The main control menu for collecting price data into AG is the 'Issues' menu - click the 'bar' icon at the top left menu or, File/New chart. The Issues menu is what you use to first load/display a chart; the 'Load Page' icon, 4th from left is what you will use to open charts you have Page/SavePageAs within AG.
The Issues utility converts the various file formats into AG format after being 'told' what to do. First, read my post 'Intraday data into EOD Advanced GET' at the
http://groups.yahoo.com/group/get_traders/ site which will give you an idea of the process of loading data into AG.
Next, I suggest for testing purposes you try to load only 1 stock, not your whole portfolio/s. One problem I caused myself was clicking on the 'Rescan' button on the Issues menu and ending up with 4 copies of ALL the securities from all charting programs AG found on my 2 hard drives; so the Issues 'utility' is very powerful and to be used with caution until you understand how it functions.
Once you've been able to load that 1 stock into AG and display a chart, create an AG specific portfolio. Copy the stocks into that portfolio from your other chart program that you want to view in AG, then repeat the loading process for that portfolio only. Once you have the portfolio contents listed in Issues, when the portfolio is updated by your other program, AG will collect that updated data when you first open AG without you having to do anything else, since you 'set the route' for AG to find and collect data.
Here's another AG forum:
http://www.optionetics.com/bbs/forum.asp?forum_id=54&forum_title=Advanced+Get
I tried to attach the AG 'Help' in a zip, but the file's too large, so if you need that, message me via elitetrader with your email address and I'll zip, attach and email the file to you. Wallace.