In Flash, when an object is overlapping another, the overlapped section of the existing object is deleted. This makes adjustments such as nudging new objects into place a nightmare. To avoid this, you can either create a new layer for every object you draw or group an object as soon as you draw it. I prefer grouping.
reusable graphics p. 19
Using symbols in Flash provides two main benefits: reduced file size and ease of editing.
When you create a symbol and place instances of that symbol on the Stage, your movie's file size is reduced because no matter how many times you use it, the code required to define it is only included in the file once. Each instance just points to the symbol and describes any modifications to that symbol, such as transparency or size.
Modifying work later is also much easier. Imagine that you've placed 100 blue squares (not instances of a blue square symbol) throughout your movie, and then you decide to change the color. You have to find and change all 100 squares. But if you made a symbol of a blue square and placed 100 instances, you only have to change the symbol, and the 100 instances are updated automatically.
edit a symbol p. 21
When you have an object on the Stage that is a container for other objects (groups, symbols and text boxes) you can just double-click it to "get inside" and edit the contents.
To exit the editing mode of the container, you can double-click outside the bounds of the container.
Sometimes when you draw a line in Flash, it isn't placed at the top of the object stacking order like you'd expect it to be. Instead, it is placed behind other objects. Defying the standard convention that a new object is stacked above existing objects on the same layer, Flash stacks lines based on a mysterious formula involving the line's color that only programmers could come up with!
You can do one of two things to make the line appear where you want it: group the line, which moves it to the top of the stack; or move the line to a layer above the current layer.
transform objects p. 26
When you're scaling vector objects (those drawn in Flash or imported, as in the logo file) you can increase or decrease the size without negative effect. However, if you're working with a bitmap image, you'll want to avoid enlarging it. An enlarged bitmap has to be resampled and can become distorted or fuzzy. It's best to open the image in an image editor such as Adobe Photoshop or Macromedia Fireworks and scale it to the size you need.