I installed Zorin 18 on my laptop with an Intel Core Duo 2, 4 GB of RAM, a 512 GB SSD, and an ATI AH Readon 2400 graphics card. Unfortunately, some settings, market, and file manager screens flicker slightly, and lines appear between spaces. I also have to constantly resize the settings windows. This problem didn't occur with version 17.3. Furthermore, after updating to the latest version, Brave looks terrible and crashes when opening, but this is undoubtedly due to hardware acceleration, which needs to be disabled, as is the case with Chrome (I also have to do this on Kubuntu).
I'm sorry that these issues prevent me from installing Zorin 18 on my laptop, so I reverted to Kubuntu 25.10, which doesn't cause any of these graphical issues and works perfectly (only for Chrome, I have to disable hardware acceleration).
I hope this graphical issue will be resolved, which I assume is due to some driver or Wayland, which in any case does not create any problems with Kubuntu 25.10.
Yeah, Wayland doesn’t always play nice with older Radeon drivers. If Kubuntu 25.10 runs smoothly on Xorg, you’re probably better off sticking with that setup for now until Zorin sorts out the compatibility issues. You could also try forcing Zorin to boot into an Xorg session instead of Wayland — that usually fixes the flickering and window redraw problems on older GPUs. It’s not as “modern,” but it’s way more stable for legacy hardware.
You could also try Zorin 18 lite when it will be released. It will probably run much better on your 4 GB machine than Zorin core.
I'm using Kubuntu 25.10 with Wayland, and it works flawlessly. Only with Chrome do I have to disable hardware acceleration in Chrome for it to work properly.
I hope these issues will be fixed in Zorin 18 core (I don't particularly like the Lite version).
However, graphically, I really like Kubuntu with KDE Plasma. I really like Zorin's desktop icon management, which Plasma still doesn't handle as well as Gnome.
Welcome to the Forum!
Did You tried on Zorin to switch to Xorg to check if it performs better?
No.
Why i removed Zorin e reinstalled Kubuntu.
Okay, I was only curious if it would work in Your Case. But when You have now a working System, this is what matters.
Yes, the only thing I like about Zorin 18 is that I would have liked to use it on my laptop.
I hope this issue will be fixed with the next releases, 18.1, 18.2, etc.
Zorin OS 18 Lite hasn't been released yet, how could you have already formulated an opinion, based on something you haven't tried yet? 
I guess it was a common Lite Comment and not specifically for Zorin 18 Lite.
I tried the lite version 17.3 and I don't like the desktop environment. As for the desktop environment, I prefer the core one.
But can anything be done to fix it? Perhaps the upcoming 18.1 update will improve or integrate some drivers for the ATI Readon 2400HD graphics card?
All this is part of why I just gave Zorin 18 a 3 out of 10 in my review of it. What in the heck are Artyom and Kyrill doing? More people need to start asking themselves that question if they are going to continue supporting Zorin OS.
EDIT: Here's a link to what I just posted (my review of Zorin). Link: CLICK HERE.