Why is my LabTutor experiment upload failing?

If you are trying to upload and install experiments sourced from the ADInstruments website you need to ensure that you are choosing to 'Open' the file (and thus unpack the experiment files to your local machine) as opposed to clicking 'Save' or 'Save as...' and downloading the intact installer. 
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It is the intact installer which is recognised by the LabTutor admin interface and can subsequently be uploaded.