There are 2 places where "Net profit" is mentioned; dont get mixed up
First is the applicability..there are 3 limits...NW, Netprofit and turnover..the netprofit talked about here in applicability is the netprofit as per ur last financial statements...no relation to section 198
Then when u come under CSR bracket; u have to make contribution of 2% of Netprofit (before tax) as per section198
Now there is an article by EY which has a very comprehensive list of things u include and exclude for calculating NP as per 198...search it online or send me ur email