Decryption program RSA 2048

I have an urgent problem. One of my company's computer has been hit by cryptowall 2.0 (a very strong virus, google it) I have paid the ransom and got the decrypt application, however the decryption works a little strange, it doesn't put the files exactly as they were. Images have 3-4 strange horizontal lines, docs and excels open but they have a little error on page.... I have some very important .bak files (that are from an important application - Microsoft Sql Server, and restored, these files won't work on Microsoft Server, some work, some don't and the application doesn't work very well) . My guess is that the decryption program wasn't written very well, so it doesn't put back the file as it should, however doc files , excel files do work. I do have the private and the public key and also the application for decrypting and i will provide them to you if you're interested (the decryption exe will be seen as a virus by the antivirus, just so you know, be careful with it). What i need is a simple program in order to decrypt CORRECTLY some important files (some have 80-100 MB - bak files). I do have the original files, i tried just with copies, since the application is rewriting the original (encrypted) files. If you think you can do this please let me know so i can send you the needed files. The encryption was made with RSA 2048 ! I don't care about what programming language you use, just make it to run on Windows. If you succeed and at least 10 pictures are perfectly decrypted and restored i will consider that you did the perfect job (that the restore is perfect now) and the project will be complete. So this is it, just one decrypting program. I already paid a lot for the ransom with my own money, so please bear with me. I can't afford too much. I need this to be done in 2 days ! I don't have the time. Please help ! Thank you.