Usually, Level 23A units have lower resale value and you need to check whether it is the same level as the water pump room or M&E room.

1. The court cases issue has been resolved?
I think the court case issue has resolved. They already start their construction.

2. Copper piping for aircond is not provided ? is this a big concern ?
It's very subjective. You may check the opinions given in this thread.

3. Check on the address, jalan tiara titiwangsa is under setapak. However, the agent told me this is a titiwangsa project ? Just wonder this project will be under setapak or titiwangsa address?
Jalan Tiara Titiwangsa 3, Setapak. Of course, the agent will say so. That's how developer and SA earn their money.

4. Hard to find the developer record. I just worry the project will stop halfway.
Nothing is guaranteed when buying new projects. Purchasers have to bear the risks when buying new projects.