Well, it's fairly clear this is a labor of love. The art style seems a bit rough, but is rather expressive with a number of animations. There's also fair bit of complexity here, along with enemies and interactions, the UI and control scheme seem's a bit cumbersome though and could use some refinement. Out of curiosity, is the game more or less "complete" in term's of levels? How many level's are there?
Few observations:
-Your control scheme needs work. Its X to talk to people, Z to advance text, A to run, D to attack, M for inventory, Enter for shop menu prompts, Z for casting spells, 1 for quick items, etc.
It would be much more efficient to have A be for both running and starting conversations, and A again for speeding up text while talking, this is referred to as "context sensitive controls", where a single button can do multiple things in different situations.
Store and inventory menu's should also follow the same paradigm, where you use A for selecting options, and either select an exit prompt or have something like D be to cancel out.
Alternatively, you could make it so by holding a button and pressing another can act as menu prompts. For example holding S and then pressing left/right for using quick items or casting spells, respectively, or up for the inventory, etc.
-T'would be nice to be able to reorganize your inventory.
-Stores should probably list how much gold you have while you shop (for reference).
-Wasn't sure how to save, until I eventually bumped into your save gem. Might be good to give the players a prompt to let them know.
As for Bugs, you can knock enemies through the electric field (such as the dark clerics), which could be an issue if you can't reach them. Also, pressing escape in the magic shop when buying things crashes out:
############################################################################################ ERROR in action number 1 of Key Press Event for <Escape> Key for object oLevel1Stores: Variable oLevel1MagicShopDialogue.sabrinadialoguecounter(100178, -2147483648) not set before reading it. at gml_Object_oLevel1Stores_KeyPress_27 ############################################################################################ gml_Object_oLevel1Stores_KeyPress_27 (line -1)