i am write check to the number of entity and used GetEntityCount () she is gives only one number, and when you create a new entity that number does not change at all. Tested this with the output message in chat
Code message in chat.
PrintToChat(client, "%d", GetEntityCount());
For example typing command "report_entities" the console I got the report: "Total 575 entities (0 empty, 489 edicts)"
i got in chat 712 and if the creation of new entity is the number does not change. And it was repeated again and again..
I have tested this issue on left 4 dead 2 dedicated server on snapshots 1.5.0-dev (Sourcemod) / 1.9.0-dev (Metamod).