It is not mid engined. Its rear engine. A mid engine car has the engine between the axles. The SBR its behind the rear axle making it rear engine.
The name of the SBR4 means... Shooting Brake Rear engine 4-cylinders... The term Shooting Brake describes a hatchback and thus, describing the SBR4. A coupe has two doors with a trunk, or for you Europeans, a boot. So the SBR4 is not a coupe, or at least in my opinion. The SBR4 is rear engined with a high powered flat four cylinder engine. A flat engine is also described as a boxer engine due to the pistons being perfectly horizontal rather than tilted like a V.
I had forgotten to include that. You are correct, but most people refer to them as a Straight X amount of cylinders.
A flat engine does not have to be a boxer engine. A flat engine is a 180 degree V. A boxer engine always has opposing pistons reaching and leaving BDC and TDC at the same time, most flat 4's as such are boxers, but not all. Most flat 6's are also boxers. Most flat 8 and aboves though, arent boxers.