The best way to learn trade system development is learning by doing. Knowing many indicators is not very important, but knowing how to test a system is important. System development is empirical, so testing is everything.

First try to understand what the parameters are doing, from their description in the manual. Some of them are for special cases only, but most - especially those that are also used in the tutorials - are essential for properly testing a system. You'll find them, under different names, in any serious automated trade software.

If you are not sure what a certain parameters does and how it affects the system, experiment with it and check the performance sheet. If then there are still open questions, ask them here.