thanks for your answer and help.
We installed the QlikView Settings Service on the IIS server and configured it like the outlined steps.
So now we only have to add '<add key="ActivateUnbalancedCluster" value="true"/>' on the QVWebServerSettingsService.exe.config and the IIS will work with unbalanced Cluster?
And here we can also customize the weights of the algorithm?
Thanks in advance.