The removal of adding modes now seems to mean that you cant make sonos play certain music. i.e. i want to create a party mode and then on triggering party mode through alexa, it starts playing my party soundtrack and changes the lights etc. but the triggers on the setup of the speaker mood music smartthings app dont seem to have any relevant triggers without the modes being variable.
You can still create Modes using the web IDE/API page.
First be sure to login to the correct IDE web page for your Shard:
As @tgauchat mentioned, It moved to the IDE, but it wasn’t removed altogether.