@Esparando You need to maintain minimum balance in savings Ac..NOT zero.
1. Yes you can apply for IPO in ASBA OR UPI mode.
2. Yes, interest will be paid, because money is just blocked never leaves youe Ac!!
3. If you do not have sufficient balance then only FD gets broken, yes there will be penalty if broken but keep sufficient balance in savings Ac so that FD does not break...
Hope this is clear..
This is in general, not specifically about RBL..