I'm sorry that you're having trouble with your content loading.
First, check that you're using the latest version of in5. The current version is v3.8.12. You can check your version by going to in5 > Info and Updates... and checking the version number in the upper right of the in5 - Info & Updates dialog that opens. If it's an earlier version, try downloading the latest version, installing it, and re-exporting your content.
If you're still having issues after updating to the latest version, would you be able to send us your InDesign file (or a sample file that recreates the issue) and your html5_output for us to troubleshoot? You can send it here: