In order to play Sandwalkers on macOS with maximum graphics settings, you need a computer with a configuration no worse than the following
Operating System:
OS X 10.9.1
Processor (CPU):
Dual-core 2Ghz CPU
Memory (RAM):
4 GB RAM
Graphics Card:
Intel Iris Pro, NVIDIA GTX 660 Ti, or AMD Radeon HD 7870 w/ 1024 MB
Storage:
1 GB available space