I am currently at end game with all upgrades. I see that the prices in the optimizer are wrong. It's not a big difference, but it's there. This also leads to the build order being a tiny bit off. Here is an example with cursor: My 254th cursor costs in game: 33,412,983,613,840,080 Price for same cursor according to optimizer: 34,091,402,524,069,056
The prices are wrong for all items except Mine, Shipment and Alchemy lab.