Here is the original Rib in the Design library. I'm not sure why you are not able to edit it, perhaps because of the save, not sure (maybe it's being referenced somewhere else?).
Maybe this time it'll work.
are you saying the 'Edit Sketch' option is grayed out? the sketch is beneath the Rib feature in the FeaturManager, but I'm thinking you know that. Hit Ctrl-Q, see if you can get it to rebuild or suppress and then unsuppressed the feature to see if you're able to then.
Oh, also, the 'edit sketch' option won't show up if you right-click on the form feature. you'll ahve to expand and go down to the sketch and right-click to edit the sketch.
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