Suggestions on product freezing on users...

My company has just released a 7 module course from storyline, and during testing, we had no reports of usability issues.

However, now that we have some clients using this product, we have had multiple cases where they, on the largest module, say that the course is freezing on them halfway through and in the middle of a quiz. Now, we are still trouble shooting this, and are wondering if this is something related to it being SCORM, or on the LMS, or maybe even something related to their computer specs? However, this is a VERY large file (the .story file is just short of a GB), and so I can understand if the output is causing issues due to the mere size.

But, no one had reported issues before this went on the server. And even some of us have tested the module on our computers from the LMS and still have not had any issues. Are there any suggestions to fix this? Is this solely on the client side of is there something we can do to resolve this on our end? Will the only solution be to break the module in two just to be file-size-safe?

Open discussion here. Taking any suggestions, comments, tips, pointers, etc...