PIE calculates the position of fixed-position target elements incorrectly, causing PIE-rendered effects to be misplaced. It calculates positions assuming the absolute positioning model.
The updatePos function of PIE.RootRenderer should be updated to correct this. This would correct the problem for all PIE effects. Position for fixed-position targets can probably be read directly from the currentStyle of the target.
The original forum post where this was discussed: http://css3pie.com/forum/viewtopic.php?f=3&t=151
Fixed in commit http://github.com/lojjic/PIE/commit/de695e55711464edc714939298d86471dcf8476e
Fix positioning of CSS3 element when target element is position:fixed…
…. Fixes issue #74.