Thanks for letting us know it's working for you!
In 1.7 of the library the analog item's core settings are always stored in FLASH / PROGMEM.
However, in 2.0 (due out shortly, honestly this time, we keep saying it, but now it is going through final testing) you have the option of creating these core data structures in RAM instead. The easiest way to use it would be to create your own menu item as explained in this page:
https://www.thecoderscorner.com/products/arduino-libraries/tc-menu/menu-item-types/. Towards the bottom of the page, there's a link to documentation for each item type.
In library 2.0 each of the constructors for menu items now has an extra boolean parameter at the end, it tells the menu item if the INFO data structure is in FLASH or RAM:
AnalogMenuItem(const AnalogMenuInfo* info, uint16_t defaultVal, MenuItem* next = nullptr, bool infoInPgm = INFO_LOCATION_PGM)
You would then insert the menu item where you want it using something similar to:
menuMgr.addMenuAfter(&menuExistingItem, &menuMyNewItem, triggerStructureChangedCallbacks);