Pink should be the transparent color in the bmp.
But that is normal with Mac, every single update something don't work anymore and developers have to run behind Mac all the time.
Why the *^%$& can't they just make a MAC that just keeps working with any app 32/64 or even PPC apps.
I hear it day in and day out from users calling me.
If everything is working fine DON'T UPGRADE or UPDATE, don't run behind Apple with their weekly new versions !

It should show like a gif with pink set as transparency:

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