A City Forgotten - Hourglass with Sand

I have tried to place the Hourglass with sand into the niche several times and nothing happens. I have moved the hourglass all over the screen but cannot get it to work. I have reviewed my progress against the walkthrough but cannot see where I may have slipped up. Does anyone have any suggestions?

Thanks

Once you have sand in the hourglass, turn it so that the sand starts to drain from the top. After that, click it on the alcove to the left of door D.

If it's visible, click the cursor tip, rather than the hourglass itself.

How do you make the hourglass turn. I have tried everything, clicked on it an it won't turn. Any ideas? Help