You can group together similar items and just put in the totals. You can use a program like Excel, Google Docs or Open Office to work out the totals, and that way you have a document that you can show the CRA if they request it.

this way works, however, this is not the best way to file the tax return. It supposed to be separated by each trading. If group all different trades together, it might cause the CRA's difficulty to understand them and add the chance for CRA's auditing. So at the end, can TurboTax add additional pages to Schedule 3 supplemental statement ?

I am having a similar problem with this. I need to add an extra form. Has TurboTax dealt with this problem?

If you will need more forms and you can't group together what you have in the two forms it would be best that you Print to Mail your return so that they get all your information.