Post any defects you find in the released or beta versions of the ImageMagick software here. Include the ImageMagick version, OS, and any command-line required to reproduce the problem. Got a patch for a bug? Post it here.
It appears your TARGA images have an inverted alpha channel. According to the TARGA specification, an alpha channel of 0 is fully transparent and 255 is fully opaque. ImageMagick uses the negation of this (0 is fully opaque) so we subtract the TARGA alpha value from 255.
Can you post a URL to at least one 16-bit TGA with alpha and one 32-bit TGA with alpha so we can test the ImageMagick TGA support. We see opportunities for fixes in the coder but we need a test image to confirm our patch is working properly.
