I was going to say:
"The hotkeys are configurable, go to options and Hotkeys tab and you can change them there, or remove them if you dont need those."
But now that i read your message you seem to be saying that CHS is triggering on AltGr+Letter when it should only be triggering on Ctrl+Alt+Letter, according to your current hotkey settings? Is it that CHS is treating the AltGr key as if you pressed Alt+Control keys and triggering the CHS action that would normally be triggered is you hit those keys?
I see now from wikipedia:
To allow the specific functionality of AltGr when typing non-English text on such keyboards, Windows began to allow it to be emulated by pressing the Alt key together with the Control key:
Ctrl+Alt ≈ AltGr
Therefore, it is recommended that this combination not be used as a modifier in Windows keyboard shortcuts as, depending on the keyboard layout and configuration, someone trying to type a special character with it may accidentally trigger the shortcut, or the keypresses for the shortcut may be inadvertently interpreted as the user trying to input a special character.
The solution for you seems to be to EITHER see if you can find how to disable this emulation thing (may not be possible),
OR, change the hotkeys in CHS to not use ALT+CTRL (or add the Winkey modifier to them).
Now I need to decide if I should change those defaults in CHS, I probably should..