i got a major problem, everything looks blocky in particle Illusion (look at submitted pics) recently i got the same problem in after effects 7.0 with the "FE particle systems plugin" (second pic) do i got a videographic-card problem or some system error within windows xp? i have re-installed both programs without success.
That looks like an OpenGL issue. Verify in particleIllusion by using "run with software rendering" in the Start - Programs - particleIllusion 3" menu or turn off hardware acceleration in the OpenGL page of the preferences.
If it works with software rendering, then it is a video driver issue. Updated video drivers from your card manufacturer's website should fix the problem.