I can't see Shadow Demon and Warlock's Golem in DotA

It seems like there are still some textures missing from the game.

Before you try anything else, attempt to run WarCraft III in OpenGl mode.

If the problem persists:

1. Repair or reinstall WarCraft III and The Frozen Throne
2. Update to the newest version

From what you said in comment, you "installed" WIII from a backup of your old PC. Windows, sadly, doesn t work like that, and a lot of thing (register for example) might be missing and end up bugging your game by missing textures.

It could also be a simple DRM, setup set a value in the register, needed to decrypt the model. Since you copied the model but don t have the key, the game ignore the model altogether.

What you should do is find your CD, reinstall from it, or if the CD is unusable but you still have a valid CD-key, go on battlenet, and download WIII/Frozen Throne from there and install properly.

If you don t have your CD(-key) anymore, try to find a friend who still have it, or buy one (I find it regulary for 10€ at video games stores, battlenet price seems to be $15).

EDIT:

I ll add that a key for WIII alone seems to give WIII and Frozen throne in battlenet, but I d like confirmation.