ConvertxtoDVD license key?

I had convertxtoDVD 4 I purchased the license and everything. but that was so long ago and I have so many lost e-mail address' that I do not know which one I purchased it with, or if its even still active. well one day convertxtodvd 4 was giving me problems so I figured I would upgrade , thinking it would automatically give me the license , since I already have purchased it. well it didnt and I dont think I should pay for it twice. now I cannot find a download for version 4 again.. and im basically screwed. Someone help me out with a license key for 5 or a non rar download for 4. Thank you.