NGUI Project Upgrade

Hello UNITY COMMUNITY, Cobalt 60 here wanting to know if the project I have almost finished with the fantastic tool NGUI will be useless if I upgrade to the full version. See I downloaded a free version that watermarks my project which would not be professional on my part. But I only want to pay the 95.00 if it wont affect all the work I have put in. That includes having to start from the beginning of the games birth to now dealing with the tool. Any Answers that are useful are greatly appreciated and will go unnoticed by me. Thank you for reading I hope you can help.