Hello,
I would suggest you use instance names for country divisions based on the FIPS convention,
for example Austria in your data.mxml is
                                        <ammap:MapArea instanceName="AT_BU" title="Burgenland"/>
                    <ammap:MapArea instanceName="AT_KA" title="Carinthia (Karnten)"/>
                    <ammap:MapArea instanceName="AT_NO" title="Lower Austria (Niederosterreich)"/>
                    <ammap:MapArea instanceName="AT_OO" title="Upper Austria (Oberosterreich)"/>
                    <ammap:MapArea instanceName="AT_SZ" title="Salzburg"/>
                    <ammap:MapArea instanceName="AT_ST" title="Styria (Steiermark)"/>
                    <ammap:MapArea instanceName="AT_TR" title="Tyrol (Tirol)"/>
                    <ammap:MapArea instanceName="AT_VO" title="Vorarlberg"/>
                    <ammap:MapArea instanceName="AT_WI" title="Vienna (Wien)"/>

instead of AT_BU should have the code either AT_01 or 01, this being the FIPS code for that area.
This way external date can be easily mapped to the ammap object, without having to do extra mapping on the server.
Or in case your current instance names are based  on a specific convention please let us know which it is.