With the TurboTax CD/Download version, you can apply your net capital losses from other years on your TP1 line 290. To access your previous year Net Capital Losses you can go directly to the QLOSS TurboTax worksheet in form mode.
Line 290 will only take the value of Before May 23 1985 from the QLOSS worksheet. And even if I override it, I need to fill TP-729-V to declare the losses which is not found in the software.
UFile, HR Block, DR Tax and TP1 among many other all support form TP-729. It seems you don't have this in your software. Is this planned to be added in the future?