AutoHotKey not working

Hi, I use Studio 2019 and have just installed the AutoHotKey Manager plugin (and also the Microsoft program mentioned here: community.sdl.com/.../3171.ahk-plugin), but I cannot get it to work. I have added 2 scripts which I found on other Studio support pages:

#IfWinActive ahk_exe SDLTradosStudio.exe
;------------------------------------------------------------------------------
;Go to next segment
;------------------------------------------------------------------------------
^{Down}::
Send ^{PgDn}
Send {Down}
Send ^{PgUp}
return

and

#IfWinActive ahk_exe SDLTradosStudio.exe
;------------------------------------------------------------------------------
;Go to previous segment
;------------------------------------------------------------------------------
^{Up}::
Send ^{PgUp}
Send {Up}
Send ^{PgDn}
return

Their effect should be to enable Ctrl+Up/Down to move one segment up or down in a text (regardless of whether or not the segment is confirmed or not - for some reason, the default Ctrl+Up/Down keyboard shortcuts in Studio jumps to next/previous unconfirmed segment even though this does not seem to be the intended behaviour), but they do not work. I even disabled the default Ctrl+Up/Down shortcuts in Studio's settings in order to avoid conflicts, but this did not change anything. Can anyone help with this, please? Of course, if anyone can tell me how to get the "normal" Studio shortcuts for "Move to Next/Previous Segment" to do exactly this rather than moving to next/previous unconfirmed segment, that would be great, although I would also like to get AutoHotKey Manager to work!

Thanks a lot in advance.

Best regards,
Dennis