Is there someone was able to reproduce the problem?
I have seen the same strange behavior on my project but I was not able to replicate it.
On my case I have a double nested FOR cycle and into the internal one I do create this sequence of objects:
a) 1 sprite with a Boolean instance variable and a number instance variable an animation (0 speed 2 frame). The variable is set just after the sprite is created.
b) 1 Sprite font with a number instance variable. The variable is set just after the sprite is created.
c) 1 sprite with a number instance variable, an animation (0 speed 4 frame). The variable is set just after the sprite is created.
what happen during debug (a breakpoint is enabled to inspect the behavior) is that:
a) the first create instance of the sprite appears just when I set the instance variable. Subsequent cycles create the object as expected.
b) no problem for this sprite.
c) the first sprite doesn't appear even after the variable is set. In this case when both FOR Cycles completed I'm able to inspect the sprite (which is still invisible, set to frame 0 that exist and should show something like the other created). If I change manually the frame to 1 and then to 0 and click STEP debug button to let the runtime proceed of one step the image appears (!)
At the moment it is all I can do to help.
Hope this will help to focus on something can cause this strangeness.