The nether restriction was due to our old host, I fixed it today and nether is being reset as we speak.
Maybe the trade o mat was out of stock?I will be happy to help you with it in-game,Just open a /ticket and make sure to say its for blackie only.
The energy condenser is for wizards but for the emc farm requirement you can /ticket and admin to place it for you aslong as you provide him with the supplies.
When I protect the land I usually dig 10-20 blocks under the house depending if they have a basement but you can request it to go down to bedrock and up to the sky.
Don't be scared to open tickets.