[For 1.8] Thank You/Like System v3.3.5 + MyAlerts support

[Ruffian]

I copy the files and folders (Thank You/Like System v1.9.10 + MyAlerts support) on their forum. I go to the admin panel, trying to go to the plug-ins. I get a 500 Internal Server Error! Deletes a file (thankyoulike.php) from the folder plugins everything works fine.
Version MyBB 1.8.6.
Installed plug-ins:

• MyBB Default Avatar Fix
  
• MyCode: [spoiler]
  
• Portal ReadMore Button
  
• ProStats
  

Help, how to make the plugin work.
I apologize for my bad English.