Thanks for the report.
You are right, limit/offset via keyword arguments is broken in current version. I will fix this ASAP.
Until this is fixed you can use offset/limit via slicing:
>>> time_entries = redmine.time_entry.filter(project_id='foobar')[:50] >>> len(time_entries) 50
This behaviour is documented in the Operations section of the docs.
Let me know if this works for you. Thanks.