Got this error message when leaving the hotel:

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FATAL ERROR in
action number 1
of Draw Event
for object building_mall2:

Fatal Error: Can not create vertex buffer of size 147456 bytes
6333 vertex buffers allocated with total size of 714656 KB
at gml_Object_building_mall2_Draw_0
############################################################################################

Looks great! I did run into an error trying to leave the initial place (hotel?) which stopped the game for me. Seems really interesting so far though.