Greetings,

While testing with the Teleport Pipes, I've noticed that they only work when one pipe is in "Send Only" mode and the other in "Receive Only" mode, but when both are in "Send & Receive", the teleport will not work (but if one is in "Send Only" OR "Receive Only" modes and the other is in "Send & Receive", they will work), it will teleport some items to the other side but will eventually stop receiving and the input side will start to throw items out of the pipe, droping them (it is like the receive function of the "Send & Receive" mode is broken).

And if the "Send & Receive" mode is enabled, would not it be correct that in the orange box on the right side of GUI should display all the inputs and outputs, and not just all the outputs (the way is being displayed indicates that the Teleport Pipes with "Send & Receive" mode are only behaving like "Send Only" mode...)?

The versions I'm using are the following: Minecraft v1.7.10, Minecraft Forge v10.13.4.1558, BuildCraft v7.1.19 and Additional Pipes v4.7.5.

Sorry if I misspelled any word/sentence, english isn't my native language. Thank you for your time.

The GUI thing is kind of intentional, because Minecraft GUI programming is hard and I am rather lazy. I agree that it's very unintuitive though. I'll try to look at it when I have some time (which, because my life is crazy right now with competitive robotics,may be a month or two).

Also, your English is really very good. I wouldn't have noticed that you aren't a native speaker. The only issue is "the way is being displayed " should be "the way it is being displayed". Not trying to nitpick, just letting you know.

Ha ha! I figured it out! It turns out that when an item is teleported into a Send & Receive teleport pipe, the pipe would try to teleport it back to the sender, and it would get stuck in an infinite loop until the item got randomly spat out.

I added an NBT tag that is set when an item is teleported so that the receiver pipe knows not to teleport it again, and it seems to be fixed.