FERMI-LAT HAS DETECTED LONG-DURATION>100 MEV GAMMA-RAYS CONTEMPORANEOUS WITH SEPS IN MANY FLARES WITH ASSOCIATED FAST CMES INCLUDING THREE ORIGINATING FROM ACTIVE REGIONS (ARS) BEHIND THE LIMB (BTL). THIS AND OTHER EVIDENCES POINT TO THE POSSIBILITY OF PRODUCTION OF GAMMA-RAYS BY PARTICLES ACCELERATED AT THE CME-SHOCKS WITH THE BTL FLARES INDICATING CONNECTION OF THE CME-SHOCK TO AREAS ON THE SUN FAR AWAY FROM THE ARS. OUR PRELIMINARY MHD SIMULATION SUPPORT THIS VIEW AND PROVIDE DATA (E.G. FIELD CONVERGENCE ALFVEN AND SHOCK SPEED COMPRESSION RATIO) USEFUL FOR STUDY OF THE ACCELERATION-TRANSPORT PROCESSES. WE PROPOSE SIMILAR INVESTIGATION OF TWO OTHER PROMISING X-CLASS FLARES WITH BROAD COVERAGE OF RADIATIVE AND PARTICLE SIGNATURES.