I like what you are trying to do here, and you definitely exposed a pretty large issue with the way tag works with cssModules but I don't know if this is the best way to solve it.
We do not want cssModules being passed down when the Tag is not a reactstrap component, but we don't know what Tag is when it is a component. Several places you can pass one reactstrap component to another as a tag and it would make sense, and in those cases, the component passed as the tag would not receive cssModule.
The larger change would be to change the way css modules integrate and using something like a wrapping provider which exposes the modules in the context and have each of the components use the context to get the modules... but IDK if that is wanted as this project aims to be simple and not use context except for where absolutely necessary.

Thanks for the feedback, I see exactly what you mean. I've removed the changes to ButtonGroup. The other three changes seem, less problematic, is that right?

I'll give more thought to the ButtonGroup and if I come up with anything I'll let you know.

@TheSharpieOne - on reflection, I'm not sure changing ButtonGroup was the right plan anyway.

The idea was to be able to give ButtonGroup a CSS Module that would style its child components, but I think this will really be easy when webpack/css-loader#520 is resolved.

Please let me know if you need anything else from me.

Hi guys, thank you all for this fix. @TheSharpieOne when we can expect this fix in npm release? :)