Modders over XDA Forum have succeeded in flashing CyanogenMod 13 or CM13 ROM on a Lumia 525. CM13 is based on Android Marshmallow and it is quite a feat to get it working on Lumia 525. Modder has posted two demo videos of CM13 running on Lumia 525 which you can check below
What is more even interesting is the promise to bring it to Lumia 520 too in future. Here is a list of what works and what doesn’t, after Android Marshmallow port on Lumia 525, for now.
Touchscreen works, but needs some calibration
Virtual buttons (Back, Windows, Search) not works yet
Sound not works yet
Modem not works yet
Wifi not works yet
Follow the development over this XDA Thread.
Thanks JLIT99 for the tip. Cheers!!