In technical writing there is emphasis on clarity. Often grammar rules are not followed. The past tense of the verb run is "ran." The past tense of the verb come is "came." The past participle of the verb run is "run." The past participle of the verb come is "come." Do not confuse the past tense with the past participle.
So these two sentences are grammatical: The email has not come yet. The script has not run yet. These two sentences are also grammatical: The emails have not come yet. The scripts have not run yet.
Some authors say that ungrammatical published articles can ruin a reputation. We are skeptical of this, but we appreciate it when articles adhere to the rules of English. For good books on English grammar, you may want to read Strunk and White, a book by Adams Media, or The Chicago Style Manual.