How can I replace a texture on the "Static Object"?

[Frontcannon]

Thanks. But there is some kind of problem, or I just do not understand something: I copied these files from the redist\static_objects\castlebase\wall into the folder I created: (files for the default castlebase wall)
Castlebase_wall.dds
Castlebase_wall.mat
Castlebase_wall_spec.dds
Castlebase_wall_nrm.dds
default.msh
default.dae

I edited the Castlebase_wall.mat, so it has the texture I want now.
I tried to look into the folder through the model editor, but it seems to only open .ent files.

What am I doing wrong?

Maybe load the castlebase object of which you modified the texture!