Is a female author sinful for writing a book about marital relationships without alerting readers to the condition that electronic games must be free of Sharia prohibitions, within the context of her discussion on how a wife should deal with her husband's interest in these games? And what should she do about this, and about the copies that have been sold?

There is no sin upon you for writing about electronic games without warning against their Sharia (definition)-related pitfalls. The default understanding is that when a Muslim mentions an action or a transaction, it refers to its correct, Sharia-permissible form. However, it is preferable to draw attention to avoiding Sharia-related pitfalls and the importance of preserving time.