You got the most important part right… Ezcad2 control board… Great!
If you haven’t been running LightBurn, please wait for the Galvo laser to arrive before downloading and installing LightBurn. It will help you make the most of your Free Trial.
I run LightBurn on a 64 bit Win 7 machine. Most of my daily-driver tasks can be handled with a Win 10 Laptop.
Tell me the specs on the oldest Windows or Mac computer you have kicking around. Start it up, view the System Info and capture the screen so you can post it here and share all the details and we can advise further.
Let’s look at your oldest computer first. You could easily be fine with a hand-me-down. 
Download the free trial and enjoy a fully functional version of LightBurn for 30 days. After you get this thing going, and when you’re ready, you sign up on the commerce page that you’ve linked and ‘Buy the key’ for the Galvo License - we occasionally call this a “Galvo Key”. You get an email (in an hour or two after your purchase) with a code that you copy from the email and paste into LightBurn. The Galvo Key will come with the GCode (smaller retail diode laser engraver) key.
If you have a Ruida, Trocen or TopWisdom “DSP” controller on any of your CO2 lasers you can upgrade your Galvo Key and “Add DSP” to cover this type of controller. If this upgrade works for one of your CO2 Lasers, with this upgrade you can control any laser engraver that we support. “Galvo Key + Add DSP”
We’re looking forward to seeing your computer specs here… Please do share… and congrats - you’re well on your way!
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