Sorry to correct léonie but I think it is important to be precise with the explanation because it could be potentially confusing.
GarageBand has two almost identical looking Automation buttons. One is a little bigger and rectangle and the other one is a little bit smaller and square.
View Automation (Show/Hide Automation)
The single button (bigger, rectangle) on top of the Track List is the “Show/Hide Automation” button or “View Automation” button. This button DOES NOT enable Automation. Automation could be enabled and running on your Project while this button is off. That means, you just don’t see the Automation controls.
So anytime you want to create/edit Automation, you have to turn this button on in order to have access to the controls. The button toggles the visibility of three controls on each Track
- The Automation Button (on/off)
- The Automation Parameter Button
- Automation Lane
Enable Automation (Track Automation on/off)
This Automation button (smaller, square) is only visible (on all Tracks) when the “View Automation” button is on. It turns the Automation for this Track on or off. It does not effect the actual automation data (the Automation Curve) you have programmed on the Automation Lane, it only bypasses it when turned off. In that state, the Automation Curve is grayed out. Please note that you can still edit the Automation Curve, even if the Automation is disabled on a Track.

About the other question with the Effects.
GarageBand X only lets you access AU Plugins, either the few internal or the ones you install yourself. The other effects in GarageBand 11 you are referring to were Logic Plugins that GarageBand had access to. These effects are still used when you load various Patches, however, and this is a major letdown, you don't have access anymore to add them to your Track.
And even if a Patch uses those Plugins, you only have limited access to edit its parameters. Only what is provided throughout the Smart Controls window. The only exception is the Channel EQ, the Amp Designer and the Pedalboard. For those three, you have full access to all its parameters.
Hope that helps
Edgar Rothermich
http://DingDingMusic.com/Manuals/
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