Internal Memory and microSD cards

I'm a newbie to GPS units and have just bought a Garmin GPSMAP 60Cx.
This has a 512MB microSD card. I bought a book and CD (with tracks and
waypoint files) of walks in my area, and would like to import all
these into my unit. However, when I get half way through this, the
unit truncates the tracks and only some of them then appear on my
unit. I cannot find in the manual how I can transfer the tracks that
have been loaded into the internal memory to the microSD card. It
seems as though any information sent to the unit via the software will
only be accepted into the internal memory, and information on the
expansion card doesn't seem to be accessible in normal use by the
unit.

Am I doing something wrong, or have I got a setting wrong somewhere?
I've read the manual over and over but can't find the answers. Any
help or advice will be gratefully received.

megamixmiwrote:

As a map author and publisher myself, I would want to know if anyone
is having difficutly using the information I provide. Furthermore, I
would stop whatever I was doing to make it right. Have you tired
contacting the author? If that fails, I would try importing the data
to a GPS mapping software. Have you tried to open the data in
MapSource? There are other utility programs like ExpertGPS that can
simplify data transfer to your GPS.
Just curious... what book comes with CD of tracks and waypoints?
- Doug
More about GPS utility software here:
http://travelbygps.com/authoring.php#gpsmaps