1 - You're placing them in an inappropriate place. StrategyParameters (Straps) should be class level variables. Furthermore, the CreateParameter method should be called in the constructor of the class.
Check out this illustrative tutorial in the WealthScript Programming Guide: Programming Trading Strategies >
Strategy Parameters.
2 - Currently, by removing a parameter from the Strategy Parameters box of the Optimization Control inside the Optimization tab. If memory serves, restoring the WL4-like functionality of enabling/disabling a parameter by using a checkbox is a registered feature request (Robert please correct me if I'm wrong).
3 - Probably because you're optimizing in Raw Profit mode? In this case, multiply the 250 parameter combinations by the DataSet symbol count. Switch to Portfolio Simulation mode, disable on demand data update (greatly speeds WL6 up in general if you keep your DataSets up to date), run the code below, do you still see it? What kind of DataSet you're running it on (symbols, bar scale, data provider)?
4, and 5 - Run the corrected code first:
CODE:
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