Push-pull won't work

I downloaded some free plans for a bunk bed which I’m modifying to my own liking. All was going well until I realized I can’t push-pull any faces. Nothing is locked, no groups… I don’t know what else would prevent this.

Plans attached.

Thanks in advance!

Bunk Bed (1).skp (242.5 KB)

Everything in the model is made of Components, you need to open the component to edit it. Easiest way is to double click it.

Excellent, thanks!