A project of a Penal/Criminal Code should not be something simple like describing a bunch of crimes and its punishment. A 'Code' is a systematized, coherent and unified body of rules of law about a specific subject. In this case, this code deals with crimes, and not about something else. Criminal procedure should (or could) have its own code (as it is a subset of procedural law branch).
This hypothetic code could be divided in two parts:
1.- A chapter about general criminal law principles and concepts.
2.- A chapter about every single offense typified and liable to prosecution.
The 1st chapter deals with subjects such as
a) what is a crime and what requires to be a crime,
b) if there will be grades of crimes and offenses (such as contravention/infraction/minnor offenses, crimes as such...),
c) which principle about causation will be used to be someone declared liable,
d) when a crime is considered commited upto completion or if it was an attempt that was frustrated,
e) the core principle of 'Non bis in idem' or 'Double jeopardy',
f) jurisdiction of the Asgardia's criminal prosecution,
h) types of punishments, etc. (this should be completed with help of criminal law theory, doctrine and jurisprudence)
The 2nd chapter deals with every act punished. This could be subdivided according to the legally-protected right affected, such as offenses related to the 'life', 'liberty', 'property', 'security', 'peace', 'economy', offenses against the government and its proper operation, etc.
Every offense should have a clear description of the act undesired and a punishment when committed.
What acts should be punished? It depends on what the society of Asgardia wants. I suggest to begin only with the basic: homicide, kidnapping, theft, fraud... and crimes against the nation Asgardia.