With google traduction  :
Hello every one, is it possible to store a tilemap in a secondary program, and call her when you want (to reduce the RAM used, and to store more maps).
My tilemap looks like that : [0000000] -> gbd1
                                        [10000...
 Thank you 

This tutorial wil teach you how to use appvars (it teaches some other things but the appvar is the most interesting variable for your problem).
Basically, what you do is creating a program to create the appvar and put your map(s) in it, then archive your appvar then run your main prog that will read into the appvar. However, this method doesn't work for "dynamic maps". I mean that you won't be able to write to the map without unarchiving the appvar (but you stil can unarchive it )

edit: ninja'd

Using Getcalc to find archived files does not return the pointer to the file.
You use the file itself, like
Output(0,1,{Y1}^r►Dec)