The font engine is causing an exception to be thrown and blank pages rendered when used with the attached 9252.pdf. Disabling the font engine allows the files to be displayed correctly. Here is the 4.0.1 Pro exception:

FINE: Error initializing Page.
java.lang.ClassCastException: org.icepdf.core.pobjects.Name cannot be cast to org.icepdf.core.pobjects.Stream
at org.icepdf.core.pobjects.fonts.nfont.Font.init(Unknown Source)
at org.icepdf.core.pobjects.Resources.getFont(Resources.java:234)
at org.icepdf.core.util.ContentParser.consume_Tf(ContentParser.java:2020)
at org.icepdf.core.util.ContentParser.parseText(ContentParser.java:1147)
at org.icepdf.core.util.ContentParser.parse(ContentParser.java:280)
at org.icepdf.core.pobjects.Page.init(Page.java:369)
at org.icepdf.core.views.swing.PageViewComponentImpl$PageInitilizer.run(PageViewComponentImpl.java:1088)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
at java.lang.Thread.run(Thread.java:637)