Xadrian uses an algorithm which concentrates on keeping the number of factories as low as possible. This can result in a slightly higher resource surplus compared to other complex calculators which may use a different algorithm. In most cases this is a good thing. Fewer factories means a lower total price and slightly higher surplus means that the storages are filled in less time and the complex can run smoother. In some cases the resulting complex is slightly more expensive but remember that you have to build less factories which means spending less time. And time is money.
Xadrian automatically uses the language of the operating system. If for some reason you want to force Xadrian to use a specific language you can set the environment variable XADRIAN_LANG to en or de. Consult the manual of your operating system if you don't know how to set environment variables.