You can notice that GUI on Synergy went wrong after latest Half Life 2 (and episodes) updates.
Current game state have such problems like:

• no additional ammo count display
  
• suit energy text cuts
  
• hud square at the center of the screen
  
• .. some more gui issues

Addon: https://gtm.you1.cn/sharedfiles/filedetails/?id=3253975798

Manual installation:
all of this can be fixed, you need just to download vpk file by link below and place it in the path:
\your Synergy installation path\synergy\custom\
for example: and start your game (if it was already running - you need to restart)

VPK file with fixes included:
Google Drive [drive.google.com]
Yandex Disk [disk.yandex.ru]