SimToolkitPro relies on SimBrief profiles IIRC. You can customize a SimBrief existing aircraft with SR22 / SR22T weights but it will still be close to pointless (as the rest of the performance calculations are based on non-editable data). You'll need to ask the dev on the SimBrief support forums to add an SR22 / SR22T profile, but it very rarely happens for him to add GA profiles