This sounds like a graphics card issue. The missing textures might be caused by an out of date or buggy graphics card driver or an issue with overheating.
First, a few general things to check - is the game patched to the very latest version available? Also, if you're overclocking or otherwise have modified the system, turn that off.
The first step to debugging a graphics card driver issue is to try installing the latest drivers from the manufacturer's (in this case, ASUS) website. If you've tried this and it's not helping, try getting the latest drivers for your laptop's chipset from AMD. It's become less possible to do this in recent years; I can't get generic AMD drivers for my laptop's chipset because the laptop manufacturer forbids it, for instance.
The "freezing after x minutes" problem sounds like it could be a symptom of overheating. Is your laptop sitting on something soft, and perhaps blocking the airflow? Make sure that there's plenty of room for air to circulate. You can also place the laptop on a cooling rack (like what you'd use to cool cookies in the kitchen) to see if that doesn't help.
If you've had it for a while and/or it is in a dusty environment, you might want to consider cleaning the fans and exhaust vents with a bit of canned air. You can get canned air at office supply stores. Make sure you keep the can upright, otherwise there's a chance it will blow a super-cold propellant onto your computer, which can cause problems.
If it's still freezing, it might be a good idea to contact customer support for your laptop. They may know of 3D graphics issues with your particular model, although in my experience customer support tends to have a tough time diagnosing these sorts of issues, so consider it a last resort.