The goal of this study is to estimate the critical point of classical helium. The model is a highly accurate ab initio based potential for two-body and three-body interactions. The proposed methodology is to perform GEMC simulations and extrapolate to the critical point. Since it was straightforward to apply a tabulated potential in Towhee MCCCS. However, Towhee does not allow for tail corrections with tabulated potentials. Two approaches are used to account for this: 1) A systematic investigation of the cut-off dependence by increasing the cut-off between 0.8 and 2.2 nm. This also requires much larger systems and, therefore, the cut-off dependence may be convoluted with finite-size effects. 2) Implementing full potential. We decided to use the Fortran90 code Cassandra, since we already have the full potential in a Fortran90 code and we have worked with the developers of Cassandra previously. The implementation is rather straight forward as we simply need to modify the Cassandra energy_routines module. Results are forthcoming.