Placement of a MFSU in the mining world results in you not being able to access the machine to check charge or place items, also trying to flip a mv transformer has no result but uses the wrench as it would normally.
All IC2 machines in the mining world flip and are un-usable from what I have found. Mod addons to IC2, seem to not screw up though, which is weird.
If you die in the mining world everything you have with you is gone forever, getting back to death point fast dose not help and I am not talking about dieing in water or lava.
I found that it does rotate it but it does not update the visual of the block. You can test this by right clicking a side of it, the first use will rotate it, the second will break it, yet the visual of the output does not change. I have not heard of this, people have died in the mining world and had no problem retrieving their items. In fact in the mining world if the chunks are not loaded the items can last a lot longer than 5 minutes. People have also died in the overworld, myself included, gotten back well before the 5 minute time limit and their items are gone. This seems to be a random issue, not just with the mining world. I was in my basement and when I died I returned very quickly and all my stuff was gone, no lava, water, or mobs around. I just forgot I did not have my jetpack on, fell, returned and nothing was there.
No. I have died 5 times in the mining world, and my items are always there when I get back. The items do not immediately despawn. MYTH: BUSTED.