Adding another circuit to and old cu

[Lexicon]

I need another radial circuit adding to our cu board to supply a new shed / workshop. We had an an eicr done before moving into this house a year ago and the cu was deemed unsatisfactory because in does not comply with current standards, being installed in 1979. It does have rcd protection rated at 100ma.
Can a new circuit be connected under current legislation? or is a replacement CU mandatory?

 

[Chewbacca]

Can you post a picture of the old board.