Dear Mariano,
Please provide the HANA Studio version you are using along with HRF DU version. Incase you are using the HCP Tools kindly mention the HANA Modeling Tools plugin you have installed in Eclipse Mars.
You are facing this issue as the HRF Tools HANA Studio plugin you have installed is not compatible with the HANA Modelling Tools plugin.
Write to me directly incase you are facing trouble finding these versions. Not satisfied pleased do raise an incident on component HAN-STD-DEV-RUL
BR,
Ramana