Howdy! I bought the game today and have been enjoying it immensely! It's quite the challenge, even on normal difficulty!

The only downside is the game crashes every time I exit it. I'm not using GOG Galaxy and instead installed it using the downloaded files & installer.

My system:
AMD FX-8350 (stock speed, stock cooler)
ASUS M5A88-V EVO Motherboard
AMD RX580 8GB Sapphire Pulse (stock speeds)
16GB G.Skill Ares DDR3-1600 DRAM (D.O.C.P. enabled)
SAMSUNG 850 EVO 256GB SATA SSD (OS & program files)
Crucial MX500 1TB SATA SSD (Games)
Western Digital Blue 1TB SATA HDD (storage)
Corsair G500 500x PSU
Windows 7 Professional 64-bit verson

Any help is appreciated!

The game's minimum requirements state a Ryzen 3 1200 for an AMD CPU. Yours is below that, which is the most likely cause of the crash.

Well, I had the same issue on ASUS Z370, GTX1070 and Win8.1. I changed BIOS settings from standard to better performance, installed the latest video drivers and run CCleaner Registry Cleaner. Unfortunately don't remember exactly what from described above fixed the issue but it was fixed.

That doesn't make much sense since I can play the game without issue. It just crashes after I exit it, like there's some process that isn't stopping correctly. If that's the case, I'll just deal with it.

Update:
While the minimum requirements may still state AMD Ryzen 3 1200 CPU here, they're updated on Steam and now show: Intel Core i5-760 / AMD Phenom II X4 965. The FX CPU shouldn't be the reason for this. I'm not sure what you mean by, "I changed BIOS settings from standard to better performance." My BIOS doesn't have anything like that. I'm using the latest graphics drivers, and my registry is clean. Not sure what's causing it to crash, but it only happens when I'm back on the Windows desktop, and the game is already closed (i.e. no icon in the taskbar).