It all depends if the license is limited to a certain number of installation, but you can always try. Give then fact that it has been released in 2006, I hardly doubt it was using online activation, therefore you can install and then activate the program. I don't think it will ask you to go online or fail to register because it has been previously registered.
I see the software is still available, but if you have any issues contact the developers: http://www.mjmsoft.com/contacts.html