software have other laws compared with music/movies for private copy law, generally (in europa except in few countrys) still not illegal downloading but that fact not make nstall/use its without buy it legal. (its a excepcion in private copy law)
You can read a book, listen music or watch a movie and make personal copys, ins’t ilegal, but for install software you must buy it and have a license (generally one for each computer), not legally pursued (except in companys) mainly because its hard doing it legally its you use for personal use but ins’t legal play a game or use eg microsoft windows without own it, the same for rip content, you must have a legal copy for “play” with it in any way (personal use)
After buy, you can do whatever with the software (Rip, Mod, Inverse Engineer etc.) for personal use, again and always if you distribuited without permiss that content its illegal even if you buy it. You only have the rights for distribuited which are written in the EULA.