An animated mesh should have a limited number of faces,otherwise the rendering will be very slow but It is the same with static meshes?
In other words , may I put some large ( up to 10 000 faces) immobile meshes in a level without affect the rendering speed?
The red. speed will change if the same mesh is converted in fbx format ?

No, any amount of polygons will in some way affect the rendering speed. An animated model will be somewhat slower than a static one. You cant render a model for "free" using some kind of magic.

the model format wont affect the rendering speed of a mesh (in most cases).

Oh
I had the idea to buy a sort of 3d drawing program in order to modelling the fornitures and the scenography in a much fastest way that the tradizional sub d modelling.
But the models are unanimable because the bad topology and heavier than the the sub D ones.

probably you can convert the models to normal maps and use a shader

then you have the form of a high polygons model but use little poligons

Nvidia Melody

The question is about the speed: Archipelis could allow me a very fast work flow (only static, background models) but an average model is over the 2000 triangles. Too much for a complex level.