After a few tries I have managed to find a solution for the breadcrumb issue I had.
In the uc_catalog.module, after the "$current = array_pop($parents);" line I added:
$current->name = tt("taxonomy:term:$current->tid:name", $current->name, NULL, FALSE);
if ($current->description) {
$current->description = tt("taxonomy:term:$current->tid:description", $current->description, NULL, FALSE);
}So now I get the translated term wherever I am.