questions/issues with mps.samples.matrixLanguage

Hi,I have the following questions/issues with the matrixLanguage sample

- I get two warnings/errors in the ABC solution:

1. the second line of the matix abc i underlined with "Error: Child in a role with unknown link"

2. det abc; results in a error msg: not a legal statement

this seems to be a bug in MPS ?

- I am also no able to enter the statement:

abc = abc T;

I tried with <CTRL-space> matrix transpose and I get <matrix> T; but i can not enter abc = abc T

where is the error here ?

thanks,

Berni.