Sims 2 University objects disappearing

Hello!

I'm struggling a lot with my sims 2 game recently and I have no idea what's going on. So the issue for this thread is that more and more objects disappear everytime I return to the lot. I tried finding an answer but I didn't so here it is.

So:

•I play on PC.

•I have The Sims 2 Deluxe Nightlife Édition and the University expansion 

•I didn't purchase the game from Origin. I have the original CD since 2007. Same for the University expansion that I installed via CD in 2011. 

•I do not have UltimateCollection (I don't even know what it looks like)

•I did download some custom content 

The problem is effective ins the University expansion. My Sim doesn't live in a dorm, but in a house, on the campus. I built her house and when I was done furnishing it, I saved and exit. When I came back, all the lights were gone, dressers, bath mats, and electronics. 

I also noticed the coffee maker was gone but when I tried to put another one on it, the game said there was already an item on counter and I couldn't delete counter since an object was on it. I had to use a cheat (moveobjects on) to delete it and replace it. So I re-purchased what was missing, saved and then exit the game. 

Now when I got back, the exact same things I just replaced were gone again, this time with desks, tables, sofas, kitchen appliances, and even wallpaper (a base game default one)....Also, now when I try to place an item, it doesn't tell me that the space is already occupied like it did with the coffee machine....does anyone know why it's happening and how to fix this?

*odd fact: the first glitch I noticed was with her car. It's a CC and she had it in black. I sent her buy some stuff on the campus and when she got back, her car was silver 🤔 That was the first weird thing to happen be or I exit the game and then notice objects are disappearing. HOWEVER, 4 other sims in the regular neighborhood also own this car and no problem occurred. 

I did a check up in SimPE and the system told me there are 2 package files missing (see attached photos).

What should I do?

Thank you