Resolution:
Designer freeze with following error in Designer.log

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Exception in thread "AWT-EventQueue-0" java.lang.OutOfMemoryError: PermGen space
   at java.lang.ClassLoader.defineClass1(Native Method)
   at java.lang.ClassLoader.defineClass(Unknown Source)
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This error is related to PermGen. Increase the PermGen space and its GC by adding the following line to designer.tra:

java.extended.properties=-XX:+UseConcMarkSweepGC -XX:+CMSPermGenSweepingEnabled -XX:+CMSClassUnloadingEnabled -XX:PermSize=512m -XX:MaxPermSize=512m

If this does not resolve the issue then attach the four files designer.log, stderr.log and stdout.log from "<HOME>/.TIBCO/logs" and designer.tra and submit them to TIBCO Support.