There's something not right with how Fusion is reading the sizes and coordinates of objects (width, height, Y bottom, etc.). I first noticed when "Y Bottom" of an object in my game was incorrectly reporting the Y Bottom of frame 0 instead of the current frame (1). It also happens with this test mfa (attached).
This object's first frame is 32x32px and second frame is 32x150px. When you run the MFA, the "height" of the object should be 150 (except for the very first split-second):
But for some reason, this only happens sometimes. Sometimes when I run the MFA, it tells me the height is 32:
....and sometimes when I run it it tells me it's 150: