Interesting indeed. I can help you find Roll20 Marketplace products, if you want to tell me more about it and give some examples. I have an idea what it's about (Lovecraftian horror on a train setting), but I haven't GM'd that system at all. What decade style is this? What maps do you need? Mostly train cars, interiors, with a certain historic appearance? Tokens/People? Horrors? Furniture? Outdoors?