Hi Everyone! I believe I have found an answer, at least for the Welcome Members Email. I located this information in the "Customizing the Members Area Experience" Help Page. I've copied and pasted the instructions below.
Once you get to Step 3, scroll down and click Customer Notifications. Then click Membership Welcome. You are now able to edit the Welcome Email!
This doesn't help with sending automated emails after the initial welcome, but I hope this helps anyone who needs to automate the welcome email.
Customize member navigation
When a member logs in to their customer account, they’ll see a new navigation menu, listing the gated pages in that member area. Choose how you want this member navigation to appear:
In the Home menu, click Settings, then click Member Areas.
Click Member navigation.
Choose where you want logged-in members to view their member navigation.
Click Save.