Available event id # space for user-defined system events

[vincentrad]

What is the available number space for user-defined events?

 

[vincentrad]

/id EventID : Specifies the event ID for the event. A valid ID is any number from 1 to 65535.
That answers the first question.

I guess the question now is does it matter what number I use or will using the same id as a pre-defined system event cause an issue?