Odd physics with the new 1.6 Terrier engine

[OHara]

1) The new Terrier has variants, one of which is 'bare' with no shroud.  However, the 'bare' variant still takes up the space for its shroud.  In applications like landers where things undock or dock near the engine, we need to allow this extra space. (Each lander at right damages the rover upon undocking.)

Only the Terrier has this invisible collider; the Spark for example rolls around on the ground in ways consistent with the visible shape of the variant you choose.  (The new Poodle is also missing a collider for its truss.)

I posted bug 20930. I can see no  Module-Manager patch or easy workaround (so I'm using Spark engines).  Please comment if I'm missing an easy solution.

2) The new Terrier variants (like most of the Making History engines, the Engine Plates, and Structural Tubes) cause extra drag when they are inserted into a stack.  Foxster already mentioned this for Making History engines (forum link) but now it affects stock engines Terrier and Spark.  

The 'shroud' version, behaves nearly as well as the old version. Or, we can just Advanced Search to get the old version.  Or, copy the old Terrier's drag definition into the new Terrier (Module-Manager patch in the forum link above).

In former KSP versions, there were individual 'drag cube' drag configurations for shrouded vs bare engines, telling KSP aerodynamics that the shrouds filled the space between tanks in a stack. I am suggesting Squad restore that distinction, in bug-report 20683.