It is definitely worth your time to try the Demo. It is actually a full-up program, it just doesn't allow script saving.
Still, you have the resource of hundreds of example scripts. Some are quite complex, but some are very simple. And a lot of those simple ones test out quite well. And don't hesitate to post absolutely any question about using WL at their site. You will get quick answers from the developers themselves.
I wouldn't recommend anyone trading a script that they didn't completely understand, and spend much time testing and modifying. This act of "making the system your own" is very important IMO.
Another important tool for me is an Interactive Brokerage account. You just can't beat IB for low-risk testing. You can actually make a profit using very small trades. That $2 round trip commission allows good testing results for very small risk.