The decompiled and cleaned source for RegisterEventHotKey and SCRKeyboardRegisterForHotKeysWithConnection.

RegisterEventHotKey.c

class HotInputDataUnknown1 {
	0x4
	0x8
	0x10
}

class HotInputData {
	UInt32 unknown; // + 0x0
	UInt32 modifiers; // + 0x4
	UInt32 keyCode; // + 0x8
	UInt32 unknown2; // + 0xc
}

class HotButtonData { // size = 0x20
	0x0
	0x8
	0x10
	0x18
}

OSStatus RegisterEventHotKey(UInt32 inHotKeyCode, UInt32 inHotKeyModifiers, EventHotKeyID inHotKeyID, 
                             EventTargetRef inTarget, OptionBits inOptions, EventHotKeyRef *outRef) {
    return RegisterEventHotInput(new HotInputData(0x0, inHotKeyModifiers, inHotKeyCode), inHotKeyID, inTarget, inOptions, outRef);
}

OSStatus RegisterEventHotInput(HotInputData const *hotInputData, EventHotKeyID inHotKeyID, 
                               OpaqueEventTargetRef *inTarget, uint32_t inOptions, OpaqueEventHotKeyRef **outRef) {

    if ((((inOptions | 0x1) == 0x1) && (inTarget != 0x0)) && (outRef != 0x0)) {
            CGSHotkeyFlags cgsFlags = EventModifiersToCGSFlags(hotInputData->modifiers);
            if (*GetHotKeyDict()::sHotKeys == NULL)
                    *GetHotKeyDict()::sHotKeys = CFDictionaryCreateMutable(0x0, 0x0, 0x0, 0x0);
            CFDictionaryApplyFunction(*GetHotKeyDict()::sHotKeys, IsHotKey(void const*, void const*, void*), hotInputData->unknown);

            if (hotInputData->unknown->0x10 == 0x0) {
                    HotButtonData *hotButton = new HotButtonData;
                    if (hotButton != NULL) {
                            hotButton->0x0 = hotInputData->unknown;
                            hotButton->0x4 = hotInputData->keyCode;
                            hotButton->0x10 = inHotKeyID;
                            hotButton->0x18 = inTarget;

                            OSStatus result = 0;
                            if (hotInputData->unknown == 0x2) {
                                    result = CGSSetHotButtonWithExclusion(CGSMainConnectionID(), hotButton, 0x1, hotInputData->keyCode, 
                                                                          0x20, hotInputData->unknown2, 0x20, cgsFlags, inOptions & 0x1);
                            } else {
                                    if (hotInputData->unknown != 0x0) {
                                            rax = 0xffff;
                                            rcx = hotInputData->unknown == 0x1 ? hotInputData->keyCode & 0xffff : 0xffff;
                                    } else {
                                            rax = hotInputData->keyCode & 0xffff;
                                            rcx = 0xffff;
                                    }
                                    result = CGSSetHotKeyWithExclusion(CGSMainConnectionID(), hotButton, rdx, rcx, _, inOptions & 0x1);
                            }


                            if (result != 0x0) {
                                    delete hotButton;
                                    if (result == 0x3f3)
                                            return eventHotKeyExistsErr;
                                    else return eventInternalErr;
                            } else {
                                    if (*GetHotKeyDict()::sHotKeys == NULL)
                                            *GetHotKeyDict()::sHotKeys = CFDictionaryCreateMutable(0x0, 0x0, 0x0, 0x0);
                                    CFDictionaryAddValue(*GetHotKeyDict()::sHotKeys, hotButton, hotButton);
                                    return noErr;
                            }
                    } else return memFullErr;
            } else return eventHotKeyExistsErr;
    }
    return paramErr;
}

OSStatus UnregisterEventHotKey(EventHotKeyRef inHotKey) {
    if (inHotKey != 0x0) {
            if (*GetHotKeyDict()::sHotKeys == NULL)
                    *GetHotKeyDict()::sHotKeys = CFDictionaryCreateMutable(0x0, 0x0, 0x0, 0x0);

            if (CFDictionaryGetValue(*GetHotKeyDict()::sHotKeys, inHotKey) != 0x0) {
                    CGSRemoveHotKey(CGSMainConnectionID(), inHotKey);

                    if (*GetHotKeyDict()::sHotKeys == NULL)
                            *GetHotKeyDict()::sHotKeys = CFDictionaryCreateMutable(0x0, 0x0, 0x0, 0x0);
                    CFDictionaryRemoveValue(*GetHotKeyDict()::sHotKeys, inHotKey);

                    free(inHotKey);
                    return noErr;
            }
    }
    rax = r14;
    return paramErr;
}

void SCRKeyboardRegisterForHotKeysWithConnection(CGSConnectionID connection) {
    if (__NumIsEnabled == false) {
            __NumIsEnabled = true;

            var_60 = *(int128_t *)0x2adf20;
            var_50 = *(int128_t *)0x2adf30;
            var_40 = *(int128_t *)0x2adf40;

            CGSSetHotKeyWithExclusion(connection, 0x3e8, 0xffff, 0x52, 0x200000, 0x1);
            CGSSetHotKeyType(connection, 0x3e8, 0x1);

            for (int i = 0; i != 12; i++) {
                    int mod = i == 1 ? 0 : (i << 4) + i;
                    for (int j = 0; j != 17; j++) {
                            int uid;
                            do {
                                    uid = j + mod;
                                    if (j == 2) break;

                                    CGSSetHotKeyWithExclusion(connection, uid, 0xffff, NULL?, NULL?, 0x1);
                                    CGSSetHotKeyType(connection, uid, 0x1);
                                    j++;
                            } while (true);

                            CGSSetHotKeyWithExclusion(connection, uid, 0xffff, *(int16_t *)(__SCRNumPadCharTable + j * 0x2) & 0xffff, *(int32_t *)(rbp + i * 0x4 + 0xffffffffffffffa0), true);
                            CGSSetHotKeyType(connection, uid, 0x1);
                    };
            }
    }
}