Can't insert relics in Valley of Titans

The silhouette of the relic goes away whenever I move my cursor off the altar, and it won't appear if I have one of the relics on my cursor when I hover over it. I can't click on the altar to make the silhouette stay. I've restarted my game and it still goes the same thing.

Anyone else having similar problems and know what to do about it?

Holding Alt will force the relic slots to stay visible, so you can put the relics in.