I had some doubt in your initial question.

NowYOUR mistake is evident
you compose a JSON array args=[arg1value,agr3value,arg3value,..]
using %Push(..)

to %SQL.Statement this is just kind of a strange structured String
%SQL.Statement doesn't deal with JSON Arrays or Objects

with arg... you have to pass a local variable array
which is a core structure of Object Script (since ever)

arg=3           ;;<max subscript count>
arg(1)=arg1value  
arg(2)=arg2value
arg(3)=arg3value

as already described by @Julius Kavay 
 

Just to rephrase your issue:

  • you expect a JSON array of JSON objects   [{..},{..},{..} ]
  • but you get a JSON object containing that array {"cursos": [{..},{..},{..} ]}
;;  asssumptio input holds the received obj
    set jobj={}.%FromJSON(input) ; convert to obj
    set jarray=jobj.%Get("cursos")   ; content of "cursos" = [..]
    set output=jarray.%ToJSON() ; convert to  string
    

docu: %Library.DynamicObject
 

 In past (before2016),
I had 2 times the challenge to run a private training within a window of 2 years

  • Are developers generally willing or resistant to the idea of learning ObjectScript? Mostly rather resistant, but forced to learn it to get the job,  
  • Why? ObjectScript is not the mainstream. And in my geographic environment (middle Europe) demand is rather low. So it's more a curiosity skill that almost no recruiters value 
  • For developers trying to learn ObjectScript - what was that process like? classroom training + practical exercises  What were the main challenges there?
    • In-person learning?  Y
    • Online class?  N
    • Documentation?  Y
    • What were your impressions? almost all tried to map the previous experience to ObjectScript the concept of variable scoping + global variants shocked them they had massive problems following CSP=>CLS=>MAC=>INT=>OBJ  
  • How did it compare to other languages? They were looking for public examples. Support of SQL was often disappointing compared to market leaders
  • What would have made it easier to learn? pushing it to universities and technical schools instead of retreating and leaving that space to competitors
  • How long did it take to learn?    basics 2 weeks - guided development 3 months
  • Was it longer/shorter than expected?  Just a predefined schedule  
  • Easier or harder than expected? Hackers and Investigators had a clear advantage Formal thinkers suffered the most.

The main environment was a huge application Upgraded from
MUMPS to ObjectScript with a lot of old-style code using enough
ancient tricks that might "Code Quality" drive crazy.

Are there any other comments you'd like to make about the hiring
or training process that might help us improve?

My personal prerequisites list:

  • understanding Java (:= Object concept)
  • understanding SQL DBs
  • willing and able to think across the fence
  • rather exploring new ideas than varying old models
  • courageous enough to explore and fill white space on their skills map
  • digging into details

Besides the technology item:
being rather an explorer than an administrator

Typical licensing happens by user by processes - every user gets 25 processes slots
if you exceed this 25 every process consumes its own license.
so up to 25 you consume 1 license but by #26 you convert to 26 licenses consumed
then the total number of license slots counts.

But there are also other licensing models. You should check with ISC Sales or WRC which one applies. 

  • $SYSTEM.License.KeyLicenseUnits()   returns the number of license units authorized by the active key.
  • $SYSTEM.License.LUConsumed() returns number of license units currently consumed at the local instance.
  • there are more $SYSTEM.License...... that might be of interest.

Docu %SYSTEM.License