Your index is set to Topic Keywords. Try changing the index setting in Project > Project Settings, Index section to the other value.
No that didn't do it either.
I have the "Clear project cache (.cpd file) before opening any project" already enabled and still no index. I can see the topic keywords in the html code just not in the index pod.
We noticed this too in one of our long-standing projects today. Seems like a bug to me. I think you'd want to have the terms appear in the Index pod, regardless of where they're stored.
Actually, that's the way it should work as far as I understand.
Wondering if anything would change if you configured the project just to store keywords in topics?
Open the Project tab and click Project Settings.
From the dialog, choose Topics and click OK.
I'd encourage others to report a bug to Adobe about this so it's on their radar.
If it's any help, the help says the topic keywords should appear in the index, but with a slightly different icon.
Can you try manually adding a topic keyword in a Robohelp topic, just to see if it shows up? If it does, you know it's an import bug. If it doesn't, the whole feature is bugged.
1. Select a word in a topic.
2. Right-click and select Add To > Index Keyword > Topic Index Keyword