I got an x15 because logitech discontinued their g600 mmo mice.
I love that theres an option to replace my g600 but dislike that the x15 has a circular button layout instead of a standard keypad style. Plus the number progression is weird and seems like it its different just for the sake of being different.
I bought it anyways and put my still functional g600 in storage for future use.
I don't know if its because of Unleash RGB, the x15 itself, or a combination of both but when the x15 is connected to my pc and i put it to sleep, it wakes up immediately. Using powercfg -lastwake in the command prompt says that its the usb controller that is causing the wake up. I can alleviate the problem if I disconnect the x15. 
Unleash RGB is on the latest version 1.49. I'm hoping theres a solution to this
I dont have any macros on the x15 that are constantly running as well. All of the buttons are set to play once when pressed.

The problem with your x15 waking up your PC from sleep mode might be due to certain settings on your computer or issues with the USB controller.

Disabling the mouse's ability to wake from sleep did not fix the issue.
I don't think theres anything wrong with my computer because this issue didn't arise until I started using the mouse
 
What I did find was that using low polling rates was causing the issue more prominently. Usually, I'm on 8kHz but I have to switch down to 125Hz because I'm playing Remnant 2 and the game has a weird engine where high poll rate causes the sensitivity to vary wildly. On 125-500Hz, the sensitivity in-game stays consistent but causes the wake issue. I'm testing 1kHz right now and the immediate waking issue hasn't happened yet. I just wished that Unleash RGB had automatic profile switching.
 
On another note, I found that 8kHz was the culprit behind the weird window snapping issue where if you wanted to move a window to another monitor it would just stick to the side and refuse to "migrate" without violently swiping my mouse across my desk. This issue was also fixed by using lower poll rates.

If you did use the software I guess you could remap the buttons. I can kind of see why someone would want the numbers to start with the number 1 being at a different location like 12 o'clock  or 10 o'clock but I quickly got used to it and just mapped the ability I want to use to the correct button and it quickly became easy to remember.