After importing model from TD 8.1.0 to 9.X.X two types of errors occures
3 types of errors occures:
1. The model extension definition "rest" found in model is not registered in workspace -> this one can be autofix
2. The model extension definition "relational" found in model is a different version than the one in the registry -> This one do not have fix
3. java.lang.StringIndexOutOfBoundsException: String index out of range: 1
-> this one do not have fix

I`m not sure what should i send you, AMA