Unreachable codes

I can’t reach my older codes, and the main interface has changed too. Can somebody help me?Where can i find those again?

If you have code that is not currently assigned to a device, you can find it under “Inactive Models” (on the left hand bar in the IDE).

Unfortunately, right now you need to assign the model to a device to view the code.

For an introduction to the new IDE check out this screencast.
For an introduction to agents, check out this one.