Since you moved the pieces from alfaeriePNG50 to alfaeriePNG, I used the alfaeriePNG50 directory for my own conversions with showpiece.php. The main difference is that the images it produced are palette images instead of true color. However, they still have varying alpha values for the edge pixels, and in many cases, they may appear identical to your pieces. After downloading and examining the individual pieces, I found that some black pieces were not recolored properly. These include
bbadger.png, which looks grainy in its coloring.
bcamelrook.png, which has a white rook.
bcamelrookferz.png, which has a white rook.
bchancellor.png, which has a white rook.
bchancellorferz.png, which has a white rook.
bchancellorrider.png, which has a white rook.
bforwardchancellorprince.png, which has a white rook.
bforwardrookbackwardsprince.png, which is white.
bkingrook.png, which has a white rook.
bzebrarook.png, which has a white rook.
Since it's consistently the rook part that is white in most of these, I'm thinking there is a problem with the SVG files. However, when I checked some of your conversions, I did not find the same problem. And when I checked the SVG code for some of these, I couldn't spot where a different color than #f9f9f9 was used for the fill color. So I'm not sure what is causing this.
Since you moved the pieces from alfaeriePNG50 to alfaeriePNG, I used the alfaeriePNG50 directory for my own conversions with showpiece.php. The main difference is that the images it produced are palette images instead of true color. However, they still have varying alpha values for the edge pixels, and in many cases, they may appear identical to your pieces. After downloading and examining the individual pieces, I found that some black pieces were not recolored properly. These include
Since it's consistently the rook part that is white in most of these, I'm thinking there is a problem with the SVG files. However, when I checked some of your conversions, I did not find the same problem. And when I checked the SVG code for some of these, I couldn't spot where a different color than #f9f9f9 was used for the fill color. So I'm not sure what is causing this.