I encountered error running the built server executable with the new v1.1.0 release. Specifically, there's error importing the "GameLiftServerSDK" module into the gamlift plugin.
This can be fixed by going to amazon-gamelift-plugin-unreal/GameLiftPlugin/Source/GameLiftServer/Source/GameLiftServerSDK/Private/GameLiftServerSDK.cpp and change line 30 and 31 from
FString BaseDir = IPluginManager::Get().FindPlugin("GameLiftServerSDK")->GetBaseDir();
const FString SDKDir = FPaths::Combine(*BaseDir, TEXT("ThirdParty"), TEXT("GameLiftServerSDK"));
FString BaseDir = IPluginManager::Get().FindPlugin("GameLiftPlugin")->GetBaseDir();
const FString SDKDir = FPaths::Combine(*BaseDir, TEXT("Source"), TEXT("GameLiftServer"), TEXT("ThirdParty"), TEXT("GameLiftServerSDK"));
and also deleting the amazon-gamelift-plugin-unreal/GameLiftPlugin/Source/GameLiftServer/GameLiftServerSDK.uplugin file.
I expect others will encounter the same problem if you cloned the standalone code from github and directly copied the C++ Server SDK Plugin for Unreal source code into the amazon-gamelift-plugin-unreal/GameLiftPlugin/Source/GameLiftServer directory. Applying the above changes should fix the module import issue.