In Both cased these are items that you can not just buy and replace, so it adds to the frustration. but Two Sims, Two bugs.

1. A Sim bought a camera from Egypt, the kind with a zoom. Her Room Mate Bought one too. There both the same camera. The room mate's camera works but hers has no options when you click on it. I threw cheats gave her camera to an other sim and that sim was able to work it. the camera only doesn't work for her and I have to go all the way back top Egypt to get a new one if I want it.

Sim 2 Built a time machine After Multiple attempts of selecting "Invent" only to have him instead ignore me to rant on his mega phone and having him invent widgets and toys he finally learned how to make a time machine. He went to the Future and to the past. Then His wife comes home and I try to make her join him in time. But she waves and stomps her feet. Can't use an item in use. He steps out and the thing kind of opens and closes its doors rapidly. Next I see theres a woo Hoo option I try it, They make out She goes in and he walks off to look at the planets. I do it again and this time they are waving at me like they can't enter as if some thing is blocking it. So I move it to the yard for more room. Again they can't enter, some things blocking it. but clearly NOT! it's on level ground, in the open etc but they keep giving me crossed out foot prints and stomping there feet. I Sell it, Re build it witch takes all day... Try again, He goes in and she changes for work and runs for her car pool! I do it again when she comes home and it worked.

But what was up with that? so annoying to have to rebuild it from the start. What was making them refuse to enter?

and a third oddity, Twice at the park Ive seen a HUGE gathering of all the NPC proprietors gathered around an empty stage reacting to a show thats not visitable. and one time the same happened with all cooks. One of the 3 times all the sims also all had books. What?

About the camera, "throwing cheats" is a bit vague?
Did you try resetting the sim? If the camera works fine with other sims, maybe this particular sim is the problem?

As for the problem with the Time Machine. I don't think that more than one sim can travel at a time, that's just the way it is.
The routing issues afterwards, well, part of that seems just a high free will issue. Also, I don't know the configuration of the rooms or the path, but that could just be a bad case of "I want to walk where you want to walk" ending in neither of your sims being able to walk anywhere. It happens. :/

Always try to reset your sims or the objects. I'd recommend using Nraas MasterController's "Reset Everything".
But, in both cases, you don't actually have to travel again or build the object again. You can find both in Buy Mode in the Debug > Misc. section (question mark when you browse the catalogue by Function). Just open the cheats console and type in :
testingcheatsenabled true
buydebug

I had the issue again with beds. When I went to buy mode to deleet the bed it said my sim was useing the bed. when clearly my sim was not useing the bed.

I am using this thread to somehow also respond to some of your others. The issues you are having with this game are rather unusual and bizarre, so maybe it is time to go a bit deeper. If an object says that it is in use and cannot be deleted because of that then something must have happened with that Sim that makes the game think that he or she is still using it.
How are you playing this game? Do you use mods and if so which ones? Do you use cheats and do you keep them enabled after using them, like the "moveobjects on" cheat?

Sounds to me like you have a mod issue. Try removing your mods and start a new game......see if things are working.

Objects in the game can glitch out sometimes like what happened to one of my computers at the market when it stopped showing some interactions in it's menu.I had to sen my sims off the lot and retreat to edit town to enter the lot in build and buy mode from edit town to replace the glitched computer and returned to my family and got them to return to the lot.They were able to use both computers normally after the glitched one was replaced.