Czien dobre, marpilot,
Are you running X-Plane on an external disk like a USB stick, a memory card or a mobile harddisk connected with a USB cable?
Are you sure you have excluded the whole X-Plane folder for ALL antivirus programs you may have running? Many users have installed some programs "by accident" that they don´t even know about like avast antivirus etc.
I am positive that it is a problem specific to your computer, and not a problem with the plane, as thousands of other users are running it just fine. We will try to help you, but ultimately you have to find out what is slowing down access to the navigational database that is residing in the X-Plane resources folder.
Jan