I tried to install my MikroTik RB751G-2HnD as described at the hardware page. It doesn't work because of the wrong file linked.
If I use
openwrt-19.07.1-ar71xx-mikrotik-nand-64m-initramfs-kernel.bin instead of the linked one (openwrt-19.07.1-ar71xx-mikrotik-vmlinux-initramfs.elf), it's working like a charm.
Please correct it for the future...
Thanks for the info. I can correct the download link for this device, but the common procedures for mikrotik devices need to be updated too, since the table still says "vmlinux-initramfs.elf" for 64MB NAND devices. I'd appreciate if someone with more knowledge about Mikrotik devices could check https://openwrt.org/toh/mikrotik/common#downloading_openwrt_images and update it.