Alon, some quick comments:
- In Construct events, like I think you're seeing, the loop and pick are combined (e.g., your Slomper_Red Choose_random <= 0 condition). In your example, creating a separate loop and condition would take up one more line than what you have now. I would use a for loop if I needed an index value and/or really wanted to walk through the whole set of instances.
- For variables, you might want to use a single Velocity instance variable and store +/- (2,...,6) in it, which could replace your Choose_random and Direction variables. Sometimes that's better or sometimes not, and the most important thing is what makes sense to you and is easiest to work with in your project.