With version 7, the DSGE instruction is documented in the RATS 7.xx Supplement PDF file included with your copy of RATS, so I would start by looking there. We added several features and made significant internal tweaks to DSGE with versions 7.2 and 7.3--those changes are documented in the 7.3 supplement.
In version 8, you will find (expanded) DSGE documentation in the new manuals.
The DSGE support in RATS is fairly extensive, but I'm sure there are some things that are better or more easily handled in Dynare due to the fact that it is specifically designed expressly for DSGE analysis. However, in RATS you have access to all of the other capabilities of the program--data handling, VAR analysis, etc. So from that standpoint, RATS may offer significant advantages in terms of dealing with a complete analysis project.
A few suggestions:
If you have existing Dynare code, we do have a tool available for converting that code into the equivalent in RATS. There are of course limitations to this, but it can be very handy. See:http://www.estima.com/dynareconvert/dynareconvert.shtml
We do have several example programs using DSGE available. You can find some on our site and on the forum. You may want to do a search on "DSGE(" from the main (www.estima.com
) page. More examples are included in RATS 8.
Finally, you might be interested in purchasing the course materials package from our State Space/DSGE course from 2009. You can find some basic information, with links to more details, here:http://www.estima.com/courses_completed.shtml
The cost of the course materials is $50.