How to get BTCZ back

Hi guys!
Two years ago I stored my BTCZ into a Z address.
I still have the wallet.dat and I even saved the public address and secret (spending key and private key) I have them stored in a txt file .
The problem is, I need to get those BTCZ now, but I tried downloading the new wallet with the wallet.dat inside designated folder… but every time I start the app, my wallet.dat is renamed to .bak and a new one is generated, other thing that is frequently happening is the EOF error, the EOF I restart the app and it goes away, but the renaming of the wallet.dat to wallet.37434535.bak is that is annoying me the most.
Anyway, I need your help to get those coins back.
As I stored the texts of public address spending key and private, can I just use them in anyway to send it all to a new address?
How do I try to recover my wallet.dat in a easy step by step?

THANKS a lot guys!

Attempts to import the private key into the wallet, instead of trying to replace the wallet.dat