Default Karbonn A2 roehsoft RAM expander

Hello Guys!

I'm quite new here so I would very much appreciate your help. I recently updated games on my my KArbonn A2, Minecraft PE to be exact and somehow it always force closes (or lags very much). I suspect that its because my phone has little RAM. I tried using Roehsoft to cure this but its incompatible for Karbonn A2. Can anybody help me with this? I believe I needed to flash a new ROM but there are so many out there I don't know what to choose (and I also no how to safely do such a procedure). Can someone give me steps to follow? Thank you very much