Converting PowerPoint to Articulate

Hey all - just received my Articulate licence and working my way slowly through tuturials. I followed the instructions to Publish my existing PowerPoint - which seemed to work - I got the message "Congratulations etc. etc." But when I select View Presentation i just get the progress bar up and its been sitting like that for ages! Is there a maximum number of slides I can convert? Obviously I understand it'll depend how much infor is on original slides, but is their a rule of thumb to follow? Any help you can give will be greatfully rec'd. Thanks