Thanks for your suggestions. I agree that the default setting of the group selection box was somewhat confusing.
I have now made the following changes:
- Students need to actively select a group (or "myself") from the dropdown menu before booking or cancelling, they can no longer just leave the selection box in its default setting.
- There is a new global option setting (scheduler|mixindivgroup) which allows the admin to enable or disable the "myself" entry of the menu globally.
This will be part of the upcoming 3.3 release, and I have also backported it to Scheduler 3.1. (Either use the latest version from github or wait for the next maintenance release.)
Regarding the option of restricting slots to exactly one group (regardless of size), I haven't done this yet but I have logged it as CONTRIB-6880, feel free to vote/comment there.