We use the Google calendar plugin from Simple Calendar for our church website and it works very well for us. I really like it and find it reliable and easy to use. The few times I have contacted support for help, Andre Harris has been quick to respond and thorough with his help or solutions offered. I recommend this product.
Same problem. After a few hours of failed export attempts, I found this post, downgraded my plugin on the dev server and now the export works. Do I need to downgrade on the server where the import takes place also, or is the new version ok for that?