BEx Analyzer: Use Of Variable Values For Planning Sequence

Hi experts,

I want to start a planning sequence using a button item in a BEx Analyzer workbook. The planning sequence itself is defined with several variables, that are input ready. The same variables are used in BEx Queries that are bound to DataProviders in the workbook. Therefore the variables are filled by the user, if the workbook has been started. If the user wants to start the planning sequence, that is defined on the button item, the same variable values (which the user has already set in the beginning) should be used. But I didn't find a way to fill planning sequence variable from variables (like it is possible in the web interface using the DataBinding function). It seems, that it is only possible to set the variable with static values, that are defined in the button item. Am I erring in this point?

Anyone here who can help me regarding this issue?