Pi400 – Lightburn
Guess whose got Lightburn working on a Pi400?
29/10/23 – updated link for the Windows on Raspberry project
Home | Windows on R (worproject.com)
Windows on Raspberry is an awesome project and enables you to install the current Arm64 version of Windows onto your Pi giving a fully functional Windows 10 machine.
According to the website it will actually work right down to Pi2 but I tested it using my faithful pi400 4gb

There are lots of videos on line on how to do this but honestly follow the instructions on their website. They are spot on an very simple to follow and of course are the most up-to-date version of the instructions

How to install | Windows on R (worproject.com)
To get the latest version of Arm64 for Windows you will need to download it from the Microsoft Servers. This is all detailed in the instructions with an easy to follow step by step set of links.

The download/ unpack and iso creation took about 45 minutes to build the iso on my i7 desktop and once done it was just a simple case of using the provided Windows on Raspberry Imager Downloads | Windows on R (worproject.com) to burn it to your SD Card.
The card i used was a 256gb A2 card from Amazon. The first boot took about 15 minutes as it unpacks and sets up the Windows install. Once the boot has finished you are at that point in the Windows setup that you have to create your accounts and set-up networking etc, but this was just the normal process. You are running Windows!!. I wasn’t asked for a activation key – I think this is because this is a development build but I guess i may need to activate Windows at a later date. I’ll wait and see!!
Once the machine was up and running I was able to install Lightburn (i used the 32bit version though X64 app support is available in the latest insider builds of Windows)and setup up my Mini Gerbil for my K40 printer

Using lightburn on the Pi400 seems fine it wasn’t laggy and everything seemed to operate and i was able to create and burn a simple test piece. I haven’t tried any over complex images yet but I guess that’s the next step.
Why?
Well why not? The Pi400 is a cheap desktop PC. Built into a keyboard it takes up very little space and support dual monitor. It’s probably more powerful that the 8yr old Dell Laptop i’m currently using. The Pi400 is 4gb and the software limits memory to 3gb. This limit however can be disabled so if your Pi4 or later versions of the 400 has 8gb then that would be a feature to employ

Start-Up
Now to be fair. Once installed and setup I did a restart from scratch to gauge some level of performance. The boot-up to Windows login took just over 2 minutes. Now that is quite a long time (though i really turn my pi’s off) but once running the Windows experience and launching of apps like Lightburn was fine and as quick as any of my work desktops.
Legality
The website says so so i’ll go with that. I quote from their FAQ page“Yes, it’s perfectly legal. Windows images can be generated from files publicly available on the Microsoft servers.”
Conclusion
If you are running you K40 from an old laptop and have got a Pi3b, P4 or P400 give it a go. It will take up less space and probably run a damn site smoother.