Downloading "repacks" from unofficial sources (like random "Plik" or file-sharing sites) carries a high risk of malware, miners, or trojans . If you did not get this directly from the official FitGirl site, the installer could be compromised.
Version 1.46 is now quite old. The official game is currently on v1.50+ , which includes massive engine upgrades (DirectX 11 improvements), better anti-aliasing (SMAA/TAA), and reworked maps for California and Switzerland. Plik: American.Truck.Simulator.v1.46.1.0s.Incl....
Repacks are known for very long installation times because they are heavily compressed. They can often take 30 minutes to several hours to "unpack" depending on your CPU. better anti-aliasing (SMAA/TAA)