I would imagine that tooling up an old car with fairly limited appeal could be a huge risk for Schumacher, injection mould tools cost thousands, plus the amount of design resource that would be needed, as I am guesing the old drawings are probably prety poor compared to todays standards and would need re-visiting...
I raced a Cat XLS/Procat back in the day and just bought another Procat only last week, but cant say that I would splash out on a re-re Cat, would love to see one, but dont think its anywhere near viable commercially..
Now if they would just re-release the Procat body's & belts that would be great