latest version of Topo Czech is here
[Only registered and activated users can see links. ]
better to download the new one-
IMGs cant be displayed in Mapsource, you can see them in Basecamp but some maps, especially the old ones need a tweak
read

[Only registered and activated users can see links. ]
may be you can find some useful tips here about Garmin maps installing
[Only registered and activated users can see links. ]
about the unlocking message it depends on the unlocker used to unlock it-