Absolutely amazing looking! Would you ever share the tweeks you made to the system?
so my code is garbage and im sure a lot of people could do it better but this is how i did the dice and inventory:
http://slimedaughter.com/text/dice-inventory_code.txt
images referenced are from the hypercard graphics kit
it probably takes knowledge of renpy/the hypercard skin to know how to fully hook it up but hopefully that points you in the right direction!