Steven Zahm@ lebon
I do not believe the issue is the version of Connections. The major difference between the two is the code for how vCards are created which is only loaded when downloading a vCard.
Did you do any other updates in or around the same time you applied the update to Connections? If you did, perhaps there is a conflict now that was not present before. My first suggestion is to try the plugin conflict checks:
Another suggestion is to check the server PHP error logs. Perhaps there is something in there that can help narrow the issue. If you do not know where to find this, you’ll have to ask you webhost.
My last suggestion, perhaps the memory allocated to PHP is being exhausted. Try increasing it. Here’s an excellent post which describes several methods on how to do increase the memory.
Hope this helps, let me know what you learn.