there will be an update of version 4 this year.
I'm not sure has been anything major that has changed which would be relevant for the Octane 4 version of the plugin. Was there something from the Octane 2018.1, 2019.1 or 2020.1 plugins that you need in the Octane 4 version of the plugin?
Does the Denoiser in the current version.
I'm sorry - I don't understand this question.
Does Kernel-> Light ID currently work correctly? What other improvements will come for version 4?
Light ID's are not implemented - as the Octane Standalone "bit" widget is not implemented in the DAZStudio plugin. You can actually enter the binary values for the lights you need - but obviously this is a very unfriendly solution. At some point this will need to be implemented into the plugin, and is on the TODO list, but I think Octane 4 will no longer be supported by the time this is done.
Paul