Troubleshooting

I have run into the same situation, day trading is considered business activity.  As much as I have been able to gather, the T5008 should not be filled in but used to calculate business income(loss).  I am trying to understand how to fill out the T2125 as it relates to reporting a loss.

On the T2125, if I report income (sale of investments) and expenses (purchase of investments) it calculates the loss correctly. Problem - now a warning stating CRA wants me to register for GST since the Gross Income (sale of investments) exceeded $30,000.

What is the correct way to fill in the T2125 to report either day losses?
Thx!