Helping a Customer with Parallels: Will Writing Software

Dear Forum,

Hope this is the right place for my question, if not I apologise.

I work in an electronics store in England and I'm trying to find a solution for my customer. He is looking to make the transition to an iMac after good experiences with the iPhone and iPad. The only hiccup is that he uses a specific piece of will writing software on his PC, and needs it to work on OS X, otherwise he can't make the switch. I haven't used Parallels myself but have had it recommended to me countless times and so it came to mind straight way. The software is called 'Sure Will Writer' and it is seemingly only available by CD-ROM from resellers. From what I understand, the software aids the user in creating wills and then prints or exports them. Every month the software opens a website (currently via Firefox on the customer's PC) and prompts the user to enter a serial code (to prevent piracy). He runs the software currently on Windows XP.

My question is this: what are the chances of Sure Will Writer (the customer owns the software on CD-ROM) working smoothly with Parallels Desktop for Mac? We are doing our best to try it ourselves with demo copies of Parallels/SWW on our demo Macs but a Sure Will Writer demo is proving a little elusive.

Any help would be appreciated!

Thanks,
Ben