After editing a component pattern the whole assembly disappears. Parts are there, just invisible.
Sounds like a display/memory issue. Have you tried "Ctrl+Q", rebuilding is probably what is needed.
Check the Solid Bodies folder to make sure the bodies have not become hidden.
I have one model that does that from time to time and I'm not sure why. The way I fix it is to scroll back thru the feature tree to the first feature then scroll back to the end. Then the geometry returns.
Hope that helps
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