Sometimes IC wires cannot be connected to each other (the farther one). I use steel wire from IE to contrast (the closer one).

And if wire is too long and you are looking at only one connector, it may only render one side.

The second one is a known issue, happens with IE wires as well and isn't really fixable (without performance issues or a lot of work). I'll look into the first one, might be an IE issue (if it is I'll probably still be the one fixing it).

It is a singleplayer world. But I forget how did I produce this issue..

I think I just place wires as normal and nothing special happens

Can you give me some steps to reproduce the first issue? I tried a couple of setups that seemed plausible to me, but wasn't able to replicate the issue at all. Also, is this on a dedicated server or in a singleplayer world (I'd guess SP, it looks like a test world)?