You are all set with Cuda/Sign Now.
You can use it independently of Nowcerts.
If you want to send a Nowcerts file/form for signature, please use the "CudaSign Special" option on the Send file/form controls.
This will send the file to your Cuda account and open it for editing (adding the "magic fields"). It opens CudaSign in an iFrame in your browser.
The option "CudaSign" acts a little different. It simply "slaps" a signature page at the end of the document and sends the form for signature. It bypasses the aditignin SignNow.
Please give it a try and let us know if you have any questions. When you test, try using a different destination email than the one used in your CudaSign account.