Heroes V version 3.1 - Official Manual ZIP with changelog
Recovered from h5.heroes.net.pl, which was recovered from heroes-fr.com, which is gone.
CH - Scripting 2.1
A lot more talking about scripting and modding is available in here.
At these times CH also created it's own guide and manual, which you can take a peak here and here. However it's obsolete and was never updated for any Add-Ons.
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