Hi Aditya

Basically I want to include the RSFS font and some user defined symbols from txexa as explained in my previous email.

I did some testing with the test code which I send and found the cause of the problem, however no solution yet.
The cause of the problem lies in the line where I say

\definetypeface[MyFace] [mm] [math] [modern] [modern] [encoding=ec]

This will enable the user defined symbols and all the math symbols as shown via \showmathcharacters are correct.

However all the matrix, mathmatrix environments don't adhere to the aligment I specify except for the first option i.e.
when I say \startmatrix[align={right, etc .... }] everything is aligned to the right but the other aligment options are ignored.

When I substitute [modern] with [default]  as in

\definetypeface[MyFace] [mm] [math] [modern] [default] [encoding=ec]

In this instance all the aligment as specified in the matrix, mathmatrix environments work. However some of the
math symbols like \Delta are incorrect. And my user defined symbols are also incorrect.

Hope you can find a solution.
Kind regards
Wim