Maybe you need to explicitly capture the errors to view the error number and/or message in a message box or something? I have no idea, just guessing based on some prior VBA work I did.
The real VB6 IDE would report errors like this at compile time.
There's no compilation (yet?) -- the code is interpreted, so runtime only.
Syntax Errors reporting was missing indeed, but I just added it now and it would show a message box (while you write the code)