Hello.
Happy to help!

What do you specifically mean by "hide preview of the avatar"?

If you refer to the fact that the avatar is visible both in the Animaze main window and also in the dedicated render window (or spout2 feed), that's done via a GPU operation of copying that already rendered image over, an operation done strictly in the GPU memory (super fast).

The avatar is not rendered twice from the ground up in either of those cases, and the performance overhead of that being visible in two places can be considered quite negligible.