Dear Sir,
Firstly It appears that you are getting lost in all this translation.
Lets try and make it simple for you.
Point 1 : You cannot file Presumptive Income in ITR - 4, that was the sole reason why ITR - 4s was introduced.
Point 2 : If books of accounts are not maintained then you can fill last 4 columns of ITR - 4, stating the details you have at your perusal and pay the respective taxes stating that No Books of accounts are maintained.
But the question which arises here is are you eligible to do it. The answer is No, since your mother still has recipts worth Rs. 15 Lacs in FY 2015-16. So it was your duty to maintain Books of Accounts or you can get it prepared now and then file your return of income in ITR - 4.
Hope this suffices and brings some amount of clarity in your queries.
Feel free to call / get back in case of further clarifications.
Thanking You.
Regards,
Rohit R Sharma
BCOM, ACA, LLB-GEN, CERT. FAFP.