• Old model ports (created before KNIME 2.0) will not be restored. For instance an executed Color Manager (which has a model output) will be loaded as configured only because KNIME 2.0+ does not restore obsolete model ports. Subsequent nodes will also be reset and need to be executed.
• Special meta nodes (specifically Cross-Validation and Looper) do not report progress.
• BitVector types revised: A new interface for bit vector values has been introduced. "Old" tables containing the obsolete bit vector definition will not be accepted by nodes using the new bit vector definition.
• Table View nodes, which were executed and saved with KNIME 1.3.x will be loaded as configured only (concept of "auto-executable" has been completely revised since 2.0).
• Old cross validation and looper meta nodes will be reset when loaded.
• Some Linux distributions complain about "Could not initialize the application's security component." Known eclipse bug, https://bugs.eclipse.org/bugs/show_bug.cgi?id=206432. Supposedly fixed in eclipse 3.4; can currently be worked around easily (create empty directory $HOME/.mozilla/eclipse).
• Some Linux distributions output weird error messages to the console when starting from a shell:

  		Locking assertion failure.  Backtrace:
          #0 /usr/lib/libxcb-xlib.so.0 [0x39a767]
          #1 /usr/lib/libxcb-xlib.so.0(xcb_xlib_unlock+0x31) [0x39a831]
          #2 /usr/lib/libX11.so.6(_XReply+0x244) [0x193f64]

  This java bug has no notable impact on KNIME's runtime behavior. Different websites suggest "patching" the jre to prevent this behavior. On 32bit systems, it is suggested to call

  		sed -i 's/XINERAMA/FAKEEXTN/g' /opt/java/jre/lib/i386/xawt/libmawt.so

  in the KNIME directory, whereas on the 64bit system, one has to call

  		sed -i 's/XINERAMA/FAKEEXTN/g' /opt/java/jre/lib/amd64/xawt/libmawt.so

Noteworthy

• The File Chooser dialog is extremely slow in Java1.6.0_07; works only with Java1.6.0_01 under Windows, reason: zip files on desktop are parsed when File Chooser is opened.