There are three options in TE blocks, public, restricted, and owner only. Currently we cannot use the restricted option. To be able to use it we need access to the "/cofh friends <add|remove|GUI>" command. Currently this command is disabled, I believe due to the fact that there are two commands under it that have quite some power, and access to the "/cofh" command is all one permission. One is "/cofh killall <MOBNAME>" and I cannot remember what the other one is. The documentation on this is quite sparse, but from what I understand the two commands (The one above and the other I cannot remember) that have potential for abuse have a built in OP check. As in those two sub commands are only accessible to OPs and the console. I would like to ask the MPT to check in on the "/cofh" command, as it is all one permission, but there are two commands of concern that are in there, but I believe they have built in OP checks. Allowing players access to at least the "/cofh friends gui" command in some way would allow a lot of flexibility with TE machines/strongboxes/tesseracts.
The issue is that our permissions system needs updating (hasn't been updated in years) in order for us to give the permission.