Install the version from the market;
Opened this version, to finish the installation of the remaining files (WiFi on);
Close Ndrive, and rename the folder /sdcard/ndrive to "Ndrivebackup". Uninstalled this version of NDrive. Then, renamed again the folder "Ndrivebackup" to ndrive (/sdcard/ndrive), put inside the desired maps and installed the version 9.2.15. Open this version and register _offline_ the maps. Dind't update at this time. Loading NDrive now should be completely functional.
Now open the market and it will update to the last version, with the maps activated.

Another way, would be, if you have root access, you can also install 9.2.15 version, register the maps, and then backup the file /data/data/com.ndrive.android/ndri3.ndr (this file contains the map activation number). Then you can install again the version from the market, restore the previous file (ndri3.ndr to the folder/data/data/com.ndrive.android) and start NDrive again.