Andre,
I am not familiar with the programming language used for Adagio modules, but there is one general underlying reason why the number may always be stored as positive ones: you can store larger numbers.
A small example:
In one byte, 8 bits, you can store values up to 2 to the 8th power, 256.
But, if you take away one bit to store the sign, you can then store values from -128 to +128.
The same is true, of course, for multi-byte integers as well.
Just a thought: I'm sure Adagio's programmers did not set it up that way just to annoy you and me

.