Can't get connection to Access Front End using Runtime

I'm building an Access database. It was originally built with Access 2007.It is split with a front end and back end.  In order to make it easy to connect  to Sharepoint I purchased Access 2013, made some further modifications to the database application and saved the file. I then purchased and set up Sharepoint and office 365 Business Essentials. 

I successfully uploaded the tables to Sharepoint and linked them to the Front End using the Import and Link Toolbar. It works perfectly.

My intention was to set my partner up with a Front End on his machine in a remote location. He enters most of the data. He is running access (Office) 2007 on his machine. I knew he would not be able to use my 2013 saved version of the Front End with his 2007 version of access so I downloaded Runtime 2013 to his machine.

He is a licensed user of office 365 and I've given him full permissions.

Here's where the problem is:

Runtime 2013 installed on his machine opens the Front End I gave him just fine. Moving to any place in the Front End application not involved with tables works perfectly. On the bottom of the application window, it says ""Online With Sharepoint". As soon as I click a command button that opens any form that involves any table linked to the sharepoint list, the cursor spins and it eventually times out. No error message.

I went on to the sharepoint site in a browser window on his machine and was able to edit or add data to the lists  without a problem. 

If someone could help me with this I'd really appreciate it.

Thanks

Mike