Stock in MegaEdit controls the following aspects of a paper:

1. Color
2. Thickness
3. Weight
4. Texture

To create a stock item for your Dynamic Products navigate to:

Catfish > Infigo Variable Data > Dynamic Products

Click Stock on the menu bar. Then click 

Edit Dynamic Stock Item

1. Name: Name of the Stock
2. Description: Description of Stock item
3. MicronThickness: Thickness of the paper
4. Price Adjustment: Each Stock Item can adjust the price based on factors
5. Weight: Weight of the paper
6. Color: Color of the paper 
7. Upload a texture: You can upload a texture file to be used in the background