Step-by-step guide on how to play WoT with Steam overlay enabled.
How to Play with Existing Account
It is most likely that this workaround will break with every update.
1. Download regular client and log in.
2. Download Steam client.
3. Rename
wgcs_api.exe
from Steam game folder to something else for backup.
4. Copy
wgc_api.exe
from regular client folder and rename it to
wgcs_api.exe
This way, Steam will detect that you are playing WoT, but WG launcher will launch a regular client instead of Steam client. If you delete regular client, the game won’t launch. And to re-start the game from Steam you have to quit WG game center after you close the game.
By ЖМИХ