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@PizzaProgram
If I were you, I would check the creation and destruction of ressources.
It's mentioned already -- heading over the stream of messages led me to the fact it may got lost.
Concentrate on the image/ressource creation and destruction - not on strings and ICS in the first place. GDI has been a problem in my company since MFC got popular (I know that MFC is not Delphi, but they share some problems - mostly hard to find bugs).
Reuse your resources, resize if memory is a concern, do not recreate them.
If this helps, you know how to keep the business running and you won time to solve the real problem.
GDI and non-UI Threads are "special" friends...
If I'm completely wrong, slap me.