Building the project is largely self-explanatory; just build as you normally would with Quartus. However, if you wish to change out assets, there are other steps you must take.
cd support
npm run build
Alternatively you can directly run the microcode assembler
cd support
node micro_asm.js ../rtl/core/rom/microcode.asm ../rtl/core/rom/microcode.rom
and convert it into hex for ingestion by the tools
node modelsim.js ../rtl/core/rom/microcode.rom ../rtl/core/rom/microcode.hex 4
For Verilator, you probably want to generate hex versions of the background and sprite assets.