Bug in Photoshop Layer styles becoming jagged on export or rasterization.

I'm having a panic inducing issue with Layer Styles. I'm making a large banner 18 ft X 7 ft. On my poster size version of this image, the second image down, everything looks fine. I'm using a combo of strokes and drop shadow in Layer Styles to add the outlines to the words in the image below. Looks fine in the poster version. In the large psb version for the banner output. When I try to export or rasterize the layer style the drop shadows go to hell. The edges become wildly off and jagged as seen in the first picture below. How can I get around this? I need to send this to print ASAP to have these banners in time for the 4th of July.
Thanks!

