Definition of algo is orders originating from machines only and not manual. So in this case irrespective of id if one places manually then it is not algo.
Waiting for SOP circular from exchanges, only after that we know the procedure.
You register only if algo fires more than 10 orders per sec, if other algo fires less than 10 per sec then no need to register it. You can run both.
One only.
Yes, order modification also counts.
Rejection above 10 will happen at broker end.
We are also waiting for the answer but we believe they may just need a small write up in brief, no code will be required.