This decision-support software is on special offer and a fraction of its old price Assistum .If you're interested in knowledge mapping, it could be worth a play. In effect its a rule-based system with the rules laid bare. So long as you're only reasoning over one case (e.g. the risk in one project) that's fine.
What I like about it is that it challenges your subjective rating of things. e.g. you may say to yourself "The risk of doing this project is medium". Assistum guides you through assessing the individual factors like market changes, innovation risk, your company's ability to run projects etc. When you finally return to the aggregate risk it may well say "You rated: medium risk, the engine rates: high risk because of the ratings you gave to factors X,Y,Z" You can then reflect on the mismatch.