Nobody for the moment have made a real miniature train simulator.
Today is done. With "Miniature Train Simulator" you will able to create a full HO network.You have a full set of track that you assemble as you wich. Add some decor and create your train to run. You can stop visualisation at any time to go to edition and modify the network at will, add a new track or completly rebuild your network

Then you can modelise with real HO model track with an accurate model that you've test for hour. You'll sure of the result before and this give you a precious help before do it in reality.

Or you can just use it like that.