Well, searching for the error message would have helped here.
As I explained in Regarding "Generate Time Data" Option in HANA | SCN
...apparently there had been a change in the SAP HANA studio so that now all SQL commands get prepared before execution...
Anyhow, I was able to do something like this on rev. 96:
create procedure run_upd_time ()
language sqlscript
as
begin
exec 'MDX UPDATE TIME DIMENSION Year 1950 1953';
end;
call run_upd_time();
...
In other words: you need a wrapper (and some more exercise with search engines... )