Hy, this topic just to highlight those two problems I found:
1 ) My companion Ed-e disappear. (I have read around forums that the same problem happen with Rex). Some info about my personal situation:
1a - I'm playing hardcoe difficult - (Italian Version);
1b - I'm sure He isn't slain in battle. When I've seen He was lost I loaded the last save, found him and choose a different way to avoid the problem, but after some minutes it happens again and again for the third time.......But this time I didn't realize it and when I done it was too late to come back
1c - When I reloaded I spoken with him and gave the order : "FOLLOW ME"....but he got lost the same way
1d - If I go to Lucky 38 and I ask Rex to go together he say to leave ED-e before, so he's alive...somewhere. I've done the same way I remember I've done when I loose him,....but no way.

The other problem is alway with ED-e (before he disappear):
2) I left him to the doctor just to comple the quest: "Ed-e my love" and she told me: "Come back in two days"......Meanwhile I've done some other quests. When I red "Ed-e is now at the Lucky 38" and I went to pick-up him.....his inventary was empty and lost all the weapons I left inside him.
The doctor just told me: "Are you ready to left Ed-e ??" nobody told me:"Be careful that by this way you'll loose everything you've inside him, like your sniper, fat man, etc.etc."
That's all
Do you Know a way to refound the disappear Ed-e or a way to left him definitely?
Do you Know where I can recover all Ed-e inventary ?
Greatings. Max

E-DE (and other companions?) can't "jump". So if you jump/fall off a cliff or something he'll try to 'go around' and end up lost. I always got him back after using fast-travel though.

Also, when you let E-DE get modified and you get him back later. It's, from a technical point of view, a different E-DE.

Kinda like a movie where they use different actors to portray a 'younger' and 'older' version of a character.

Like in The Godfather where you have De Niro and Brando playing the same character only to have Don Corleone lose his mole because Brando doesn't have one like De Niro.

It happens:
1) going from Canyon east (south of the map) to drive in
2) going from a factory to another factory in the north ovest
anyway, no hills no mountains, just waliking the street......

Haven't had that. Lost him after descending from some hills, but he was back when I fast travelled to a location.

Didn't get a chance to play with E-DE very long though because of DLC-bug.

Yesterday I had the confirm that Ed-e is near me but He's invisible (and passive), and I can't speak with him. ;(

does he still attack? can you see laser's coming from no where lol

No no - He's passive.
Today I've seen the human bug with Veronica, infact finished the game I reloaded an old save to finish the Cesar's quests, but once I'd to enter in Cesar's tent the guard stopped me 'cause I must enter lonley.....and I was all alone infact Veronica wasn't still with me....but where????....so I realilzed was the same problem with ED-e, so I tried what I've seen on youtube.....go to vault 22, and it really work, when I arrived there Veronica appears.!!........may be there's a vault for Ed-e ?? ahahehehe