Official tutorials for the Sketchup plugin are works in progress at the moment. This is also a part of a major standardization occurring across all platforms (which is in the process of being defined).
I will aim to put together a tutorial of the correct workflow for IES lights, and post it here as soon as possible. As soon as we have the standardization completed, I will likely carry this over to the OTOY docs website.
I will aim to put the workflow together for you by tomorrow at the latest. Thank you for your patience.