Hi David!
Thanks for your interest in our plugins.
We do not have any specific integrations with Memberpress, but I know some of our users do use it on their sites in conjunction with our plugins. We do not do any real user management within our plugins.
Really, the only way to be sure that it will work the way you need it to is to test it out. If you are looking for an integration with Events Calendar PRO or any of our premium plugins, we do offer full refunds within 30 days of purchase.
The client wishes users to customise their own calendar to schedule workouts and also receive SMS reminders to work out
Unfortunately, these are not built-in functionalities of our plugins. Some sort of customization could probably be done on top of our plugins to achieve that.
Let me know if any follow up questions.
Best,
Victor