Thanks for the quick reply. English is fine with me.
Anyway, I tried that before, and it didn't work for me. The reason was I was doin it wrong. In the mean time I "figured" something out so if you don't mind I'll post steps I did so someone conefused like me could use them in the future. So here are the steps:

1. Install latest version of MapSource (Win XP-SP3, or later, needed)
- do not run it yet
2. Download gmap folder (unlocked)
3. Unpack (Zip/Rar) gmap folder to location: X:\Documents and Settings\All Users\Application Data\GARMIN\Maps
-where X is drive where MapSource is installed (most cases C)
-IMPORTANT: "show hidden files must be enabled" because "Application Data" folder is hidden, that way you can navigate to that folder exactly.
3.1 After unpacking you have situation like this:
C:\Documents and Settings\All Users\Application Data\GARMIN\Maps\AdriaROUTE 3.10 NT.gmap
- that folder holds necessary files
4. Start your MapSource
- Maps should already be there and details visible.
5. Connect your GARMIN GPS device
6. Select maps you wish to transfer to device with "Map tool"
7. From the MapSource menu selcet Transfer>Send to device
- chose drive letter denoting your device and hit send

That's it.