Hi,
As per facts provided by you paid up capital is Rs. 5 Lacs and the amount you want to treat as share application money is Rs. 7 Crore.
As per my opinion receipt of share application money over and above of Authorised capital is not a default at all. Reason being share application money is not in the nature of paid up capital unless and until allotment of share against the share application money.
In other words only after allotment of share you can consider such share application money as paid up share capital. But before passing allotment resolution you have to increase your Authorised capital.
Making application to the company for allotment is just an offer pending acceptance from the company. Without acceptance the same would not be a binding contract for the company. Refer Indian Contract Act, 1872. Company reserves the right to reject the application and refund the share application money with or without interest as per the terms of acceptance of share application money.
However apart from the legality, in your case the difference i.e. difference between 5 lacs and 7 crore is quite big so the same may be questioned by ROC at a later stage.
Best Regards