It's a great tool.  I installed it and used it  but the next time I went to use it it was gone.  It had disappeared completely, even though it still showed as an installed update under Resources.  I tried a number of things but what finally resolved it was hitting the Reset Updates button.  I accepted the warning and then searched for and reinstalled all the updates.  Once that was done I had the toolbox back.  I believe this is somehow a Pixinsight problem which, hopefullly can be resolved in a future update.
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