I can confirm that Project Arachnid has a new API, which is free for all after registration (awesome!) but it is all new and not compatible with the existing implementation in Chevereto (let's call it Project Arachnid Legacy API).
I need to add support for both APIs (legacy and new) which will take some time. Talking about bad timing as this new API came just by at the end of Chevereto v4.2 sprint. Will try to add it @ some v4.2.X if there's room for it.
Do please react/like this post to push things sooner.