Leto list index out of bond (-1) what does this mean

This happends when i want to enter feat list in leto .
Any idea what is happening.

Most likely the character has an unknown feat or skill - unknown to Leto that is.

Leto reads the names for feat, skills, classes etc. from its own file (Lists.leto.xml). That’s why you’ll get error when editing a character from a module with custom skills and classes.

The advanced editor might work, I’m not sure though. It has been a while since I used Leto.