jdk-7u6-ea-bin-b20-windows-i586-debug-18_jul_2012.tar.gz bundle does not contain FX files:
bin/javafxpackager.exe
jre/bin/decora-d3d.dll
jre/bin/decora-sse.dll
jre/bin/fxplugins.dll
jre/bin/glass.dll
jre/bin/glib-lite.dll
jre/bin/gstreamer-lite.dll
jre/bin/javafx-font.dll
jre/bin/javafx-iio.dll
jre/bin/jfxmedia.dll
jre/bin/jfxwebkit.dll
jre/bin/libxml2.dll
jre/bin/libxslt.dll
jre/bin/prism-d3d.dll
jre/lib/javafx.properties
jre/lib/jfxrt.jar
jre/THIRDPARTYLICENSEREADME-JAVAFX.txt
lib/ant-javafx.jar
lib/javafx-doclet.jar
lib/javafx-mx.jar
THIRDPARTYLICENSEREADME-JAVAFX.txt

No issue with jdk-7u6-ea-bin-b20-windows-i586-18_jul_2012.tar.gz