There is a bug that prevents items subscribed to while in Steam from showing up iin the game. This problem doesn't occur if you subscribe to them in GalCiv3.

Here is the way to overcome the bug.
1. Start GalCiv3
2. On the main menu, choose New Game
3. On the Choose Civilization screen, look at the left column where all the civilizations are shown, then look at the bottom of the column to find the Steam Workshop button
4. Click on the Steam Workshop button.
5. When the workshop appears, move your cursor over any of the races.
6. Notice an icon will appear in the lower right corner of the picture of the race. It will be either a green square with a white plus or a black square with a blue checkmark. It doesn't matter what it is.
7. Click on the icon.
8. Wait a fraction of a second for it to change to the other icon.
9. Click on the new icon.
10. Wait a fraction of a second for it to change back to the original icon.

What you did with the first click is tell GalCiv3 that a change was made with items from the workshop. The second click put things back the way they were, but it still left GalCiv3 with the message that a change was made.

11. Click on "Click here to return to the game" at the top of the screen to return to GalCiv3.
12. A window with Synchronizing Workshop Items will appear. It may take a while to synchronize everything.
13. When the synchronizing is done, you will be back at the Choose Civilization screen and will see the races you subscribed to. Everything else you have subscribed to will also appear in the game.

This is method I use, and it works every time.

Thank you very much! I'll try to get that done tonight.

oh, illhave to try this, i too have this issue

ok it worked, i only had to tell one to unsub and then resub and when i exited workshop the game auto synced all of them