Type renaming seems to be broken. The error looks like perhaps the syntax has changed or there's a problem parsing the cql.
cqlsh:test> create type foo (somefield int);
cqlsh:test> alter type foo rename to bar;
<ErrorMessage code=2000 [Syntax error in CQL query] message="line 1:22 no viable alternative at input 'to' (alter type foo rename [to] bar...)">