The addon is working again. Please download the new version (1.0.7) from the website. I wasn't able to test the addon with multiple gpu's. It should work with cpu's and one gpu. It could work with multiple gpu's. I took the opportunity to fix the problem with different names (display).
I still have to fix the benchmarks which are already have been uploaded. But I will do that as soon as possible.
When you change the render device settings, the scene need to be reloaded. It won't affect your render device settings, but will reset all other scene settings you may have altered.
If the addon isn't working with multiple gpu's, please leave a message or add an issue!