update:The problems described below are fixed in ImageMagick 6.2.9-8.
If you are installing PXN8 on Windows, do not use ImageMagick 6.2.9-5 (as of writing this is the latest version). I recommend using version 6.2.5-4-Q16-dll instead.
There are a number of problems with ImageMagick 6.2.9-5 on windows.
- Blending is broken. Alpha masks can only be black & white. (no shades of gray)
- Compositing is broken (related to above). Compositing using a masks with more than 2 colors will fail
- Font Size is broken. Overlayed text will always appear in the same tiny point-size
For these reasons, I recommend using ImageMagick 6.2.5-Q16 on Windows rather than the latest 6.2.9-5 version.
I have just posted a bug report to email@example.com.
update: This is still a problem with build 6.2.9-6 (a later build).