To utilize the Biomes O' Plenty worldtype, edit "server.properties" and on the
"level-type=" line, change it to "BIOMESOP"
If a world has already been generated, you will need to delete the "world"
folder and generate one again by starting the server.

This server uses 5 gigabytes (5120 megabytes) of RAM. 
This is the optimal configuration but can be changed at the server operator's 
discretion by editing the "start.bat" file.