  In this note we summarize some of the properties found in [1], and its
relation with [2]. We comment on the construction of the action of the 11D
supermembrane with nontrivial central charges minimally immersed on a 7D
toroidal manifold is obtained (MIM2).The transverse coordinates to the
supermembrane are maps to a 4D Minkowski space-time. The action is invariant
under additional symmetries in comparison to the supermembrane on a 11D
Minkowski target space. The hamiltonian in the LCG is invariant under conformal
transformations on the Riemann surface base manifold. The spectrum of the
regularized hamiltonian is discrete with finite multiplicity. Its resolvent is
compact. Susy is spontaneously broken, due to the topological central charge
condition, to four supersymmetries in 4D, the vacuum belongs to an N=1
supermultiplet. When assuming the target-space to be an isotropic 7-tori, the
potential does not contain any flat direction, it is stable on the moduli space
of parameters. Moreover due to the discrete symmetries of the hamiltonian,
there are only 7 possible minimal holomorphic immersions of the MIM2 on the
7-torus. When these symmetries are identified on the target space, it
corresponds to compactify the MIM2 on a orbifold with G2 structure. Once the
singularities are resolved it leads to the compactification of the MIM2 on a G2
manifold as shown in [2].
