One of the challenges of working with multiple masters is how to make sure there is consistency between them. In FontLab 8, the Layers and Masters panel helps with this. When all layers in this panel are colored green, consistency exists between individual masters. If any of the layers is colored pale pink, then for that layer the starting points of the contours do not match the starting points of the contours in the other masters. And if some of the layers is colored red, then there are huge differences between it and the rest of the masters - most likely in the number of contour points, in the sequence of the contours, etc.
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