Hi Paul,
Thanks for attaching your surveys. I have tested both your Simple and Complex survey on Windows 10 and Windows 7 and am unable to reproduce the crash you indicate at time of refreshing the survey. That being said there are some differences to what I am testing with (only the xlsx form) and what you are using, which includes media files.
Can you please navigate the to the folder of your survey (C:\Users\{username}\ArcGIS\My Survey Designs\) and zip up the entire folder for the survey and attach to post, so that I can get the contents of media folder? It is possible the issue is related to the images you are using.
One thing to note is that your Complex is actually not that overly complex. Whilst it has more questions, calculations and other smarts compared to your Simple survey, this shouldn't be the problem. We often see users with 500+ questions and very complex calculations, relevants, pulldata(), images etc and the surveys do not crash, but are definitely slow to load and refresh.
The other cause could be Windows 7 SP1. We have seen in other cases where crashes occur in Windows 7 due to drivers or location settings. Can you confirm if Location Services is enabled or disabled on your machine? Sometimes this is managed by your System Administrator, which we currently have an open bug for this, as if disabled then Connect and the App will crash on Windows 7 SP1 when return to survey gallery. Navigate to Control Panel\All Control Panel Items\Location and Other Sensors to check settings.
If disabled you will see the following, if enabled you will see the settings to make changes:
Regards,
Phil.