I don't know what happened at all. after the two rooms of bubble puzzles to open gates (near the start of the game), there is a room with enemies. this is where there is a secret chest with a ring inside. I moved forward, but when I moved rooms, the music changed, the game exited full screen, and this appeared
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FATAL ERROR in Vertex Shader compilation
ShaderName: shd_pal_swapper
D3DXCompile failed - result
at gml_Script_pal_swap_set
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stack frame is
gml_Script_pal_swap_set (line 0)
gml_Object_obj_waterpal_Draw_0
please tell me what to do.