@tomleslie 

I understand ... I have just some technical problems because the system is huge.

I am not familiar with MaplePrimes and I do not know wher I can drop the file (the ".m" file or a ".mw" file where the result of an "eval' exhibits the full system)

What do usually do the "MaplePrimers" in this situation ?

@Preben Alsholm 

The title of my question is deliberately provocative : I use Maple for more than 25 years and I am 99.99.. % confident in it ... except in the present situation

I guess you felt attacked by that title and you did not read further these three lines of comment ?

Ok, that's the game and you have scored a point.

It seems impossible to load a ".m" file here.
Executing the "eval" function in a ".mw" file after the read "..../MC.m" produces a very lengthy output (20 Mo) : does it exist some "deposit" in MaplePrimes where I can drop this ".mw" file ?

Hope to read you soon, thanks for the reaction