"After writing all that material, the computer didn't save it."
The computer did not do the writing; what is actually meant is "After writing that material, I discovered that the computer didn't save it," (or, more honestly, "After writing all that material, I forgot to save it"). The subject I was omitted from the original sentence.
The positioning of limiting modifiers such as only, nearly and almost is especially important. "Only Frank dropped the bomb," "Frank only dropped the bomb" and "Frank dropped the only bomb" all have different meanings.