Normally, a Circle in SolderMask Layer, drawn correctly in PCB to expose the copper of a Via, in Top Layer only, is not showed correctly in 2D preview. The above mentioned circle is shown in 2D preview smaller. For example, I make a circle of 20 mils Width and 10 mils Radius in Top SoderMask Layer. When go to 2D preview, the circle is showed correctly this time. But when the PCB file is closed, and opened later, the 2D preview now is missing the Width parameter of those circles, they are shown smaller, only of Radius size. The circles should be of Radius + Width / 2 size. They are shown correctly in PCB Top SolderMask Layer. They are shown correctly in 3D preview. But not in 2D preview (unless they are recently drawn and the PCB file is not closed). Hope this bug can be fixed in next update. Thanks.