As per instructions given with form 112 the fine is -:
In case of delay in filing the form beyond the stipulated period, it has to be accompanied by a request for condonation and appropriate condonation fee as per the following schedule:
(i) Delay upto 30 days beyond the initial period Rs. 100/-
(ii) Delay between 31 days - 180 days Rs. 300/-
(iii) Delay beyond 181 days Rs. 1,000/-
Problem can arise if institute comes to know about the additional course. For exp. if in future you try for campus placements then it will be difficult for you to mention additional courses done without submitting 112.
So preferably if you are ready to pay fine then submit the form otherwise take risk and ignore it.