I would look into options for solving your CG/NAT (DDNS...) problems, since it's a first backup aswell. If your phone is stolen or lost, the captures from the last sync are already on your server.

Try GIMP, I switched from PS with relative ease. I made graphic designs, though.

I specifically bought my vacuum as their recommendations say. I have flashed two Dreamee D9, it worked flawless. If you want i'll look into the manual for your's to state if the procediure is the same.

Edit: just looked it up. I did UART, not Fastboot method (which is required for yours)

I highly doubt it aswell, since valetudo api is running locally. The solutions from the manifacturers always connect to a cloud as far as I am informed. Anyways i never tried any of these "original" solutions as my vacuum was never activated before flashing valetudo. It's one of my fav open source projects since the documentation is sooo good and helpful. If you want to know how I made it or need help > hmu on matrix or here. Greets

As you mentioned Valetudo: I can highly recommend it! The HA integration is very beautiful too.