The TaxAct® program does not support filing Schedule C (Form 1040) Profit or Loss From Business for those who are not a material participant in their Schedule C business. Users are not allowed to check "No" on Line G Did you "materially participate" in the operation of this business during the current tax year?. Therefore, TaxAct treats any income or loss as nonpassive. If you are not using Form 8582 Passive Activity Loss Limitations, it should not matter if you mark the box as materially participating or not on the Schedule C as that is used to determine passive income/loss limitations.
If you find yourself in the unusual situation that you do need to use Form 8582 with Federal Schedule C, unfortunately, it will not be possible to complete that return using the TaxAct program.
Note that any link in the information above is updated each year automatically and will take you to the most recent version of the webpage or document at the time it is accessed.