Questions and postings pertaining to the usage of ImageMagick regardless of the interface. This includes the command-line utilities, as well as the C and C++ APIs. Usage questions are like "How do I use ImageMagick to create drop shadows?".
ImageMagick supports transparent Postscript to GIF if you have a modern version of ImageMagick and the file only contains one page and there is a DSC comment within the file specifying a language level of 2.
Your Postscript has CMYK colors so it's rendered with a CMYK device rather than an alpha device. However, with the latest ImageMagick release, 6.2.6-6, we got the desired result by forcing an alpha device as follows:
You might be able to simply upgrade your version of Ghostscript to enable the pngalpha device. If not you can grab the source and make sure pngalpha is enabled when you build/install. Have fun.