@ecterrab : Thnx for the tip; tested it on my (more complex) case; worked like a charm :-)

Thnx, Acer, Rouben & Scot for looking into (and solving) my question.

The fact that Maple might give an incorrect answer (without any warning), depending on the formulation of the equation, is somewhat disturbing to me (coming from another world ;-) ). I'm using 2D tot assist formula conversions and simplifications (by hand). I was hoping that numerically verification of these converions would be possible without any extra "translations" or deep knowledge of Maple's innards.

Would there be somewhere, code that takes a worksheet, copies it, translates all 2D to 1D and substitutes sum, product and mopd to add, mul and irem and turns to 2D again? Looking into the programming language, I assume this would be possible, but before breaking my head, I might assume this already has been done? (a quick search in MaplePrimes however did not produce a useable hit and AI is way too buggy).

Thnx for any ideas.