Wrong Forum, better use a lite-C-Programming or Starting with Gamestudio-Forum instead.
Check the Manual, some common reasons for this error message (invalid pointers, ...) are mentioned there.
You can use sys_marker to track down the error location, example:
...
sys_marker("B01");
you = ent_create...
...
sys_marker(NULL); //reset marker
When your code crashes inbetween those lines, the error will output B01 instead of SYS.
