Here is a project that responds to a ping on ETH1 (The ethernet channel on the main/top board of the S7G2-DK board). The project has NX_BSD layer in it, obtains an IP address via DHCP, and output the IP address via USB CDC ACM to a terminal program on the host PC. This is an SSP 1.1.0 project.
I have changed the define _POSIX_SOURCE to __USE_W32_SOCKETS as it seems to effect less headers files in the GNU toolchain.
This project does take a while to build, as source for all the Express Logic components (TX, NX, USBX, NX_DHCP, NX_BSD and USB_CLASS_CDC_ACM) have to be included (rather than using the pre-built libraries) , since we have modified the ThreadX and NetX configuration for the BSD layer.
I didn't have to change any pin configuration. If, when generating the project, you choose the second option on the "Project Configuration" page, that is "S7G2-DK BSP" which is a board specific BSP, rather than the first option "BSP" which is a generic BSP for the S7G2 device, then the pins for the most common peripherals should already be configured (the pins for ETH1 are configured as RMII1, and high, or medium, drive strength, and Port 7 pin 06 is a GPIO output for the phy reset). The only other thing to remember is that the DIP switch ETH1 on the top board should be switched ON (and CAM on the bottom board should be off, as the camera and ETH1 share pins, so are mutually exclusive).