[SOLVED] SystemError when connecting to Rexster with bulbs

I have set up a Titan + Cassandra + Elasticsearch + Rexster server. Everything installed correctly and I am able to play around with the "Graph of the Gods" in the Gremlin console. I started everything with the titan.sh script.

titan/bin/titan.sh status outputs:

Titan + Rexster (com.tinkerpop.rexster.Application) is running with pid 4443
Cassandra (org.apache.cassandra.service.CassandraDaemon) is running with pid 3909
Elasticsearch (org.elasticsearch.bootstrap.Elasticsearch) is running with pid 4280

If I go to http://localhost:8182/doghouse I am able to see an empty graph called "graph".

Now I am trying to connect to Rexster from Python (3.4) using the bulbs package (http://bulbflow.com/). The code I am trying with is very simple:

from bulbs.rexster import Graph, Config
kg = Graph(Config('http://localhost:8182/graphs/graph'))

I get the following exception:

Traceback (most recent call last):
  File "/home/iulian/PycharmProjects/pygm/py/gm/graph/__main__.py", line 194, in <module>
    main(sys.argv)
  File "/home/iulian/PycharmProjects/pygm/py/gm/graph/__main__.py", line 160, in main
    kg = Graph(Config('http://localhost:8182/graphs/graph'))
  File "/home/iulian/py3venv/lib/python3.4/site-packages/bulbs/rexster/graph.py", line 56, in __init__
    super(Graph, self).__init__(config)
  File "/home/iulian/py3venv/lib/python3.4/site-packages/bulbs/base/graph.py", line 58, in __init__
    self.vertices = self.build_proxy(Vertex)
  File "/home/iulian/py3venv/lib/python3.4/site-packages/bulbs/base/graph.py", line 124, in build_proxy
    return self.factory.build_element_proxy(element_class, index_class)
  File "/home/iulian/py3venv/lib/python3.4/site-packages/bulbs/factory.py", line 19, in build_element_proxy
    primary_index = self.get_index(element_class,index_class,index_name)
  File "/home/iulian/py3venv/lib/python3.4/site-packages/bulbs/factory.py", line 27, in get_index
    index = index_proxy.get_or_create(index_name)
  File "/home/iulian/py3venv/lib/python3.4/site-packages/bulbs/rexster/index.py", line 80, in get_or_create
    resp = self.client.get_or_create_vertex_index(index_name, index_params)
  File "/home/iulian/py3venv/lib/python3.4/site-packages/bulbs/rexster/client.py", line 668, in get_or_create_vertex_index
    resp = self.gremlin(script, params)
  File "/home/iulian/py3venv/lib/python3.4/site-packages/bulbs/rexster/client.py", line 356, in gremlin
    return self.request.post(gremlin_path, params)
  File "/home/iulian/py3venv/lib/python3.4/site-packages/bulbs/rest.py", line 131, in post
    return self.request(POST, path, params)
  File "/home/iulian/py3venv/lib/python3.4/site-packages/bulbs/rest.py", line 186, in request
    return self.response_class(http_resp, self.config)
  File "/home/iulian/py3venv/lib/python3.4/site-packages/bulbs/rexster/client.py", line 198, in __init__
    self.handle_response(response)
  File "/home/iulian/py3venv/lib/python3.4/site-packages/bulbs/rexster/client.py", line 222, in handle_response
    response_handler(http_resp)
  File "/home/iulian/py3venv/lib/python3.4/site-packages/bulbs/rest.py", line 50, in server_error
    raise SystemError(http_resp)
SystemError: ({'status': '500', 'server': 'grizzly/2.2.16', 'transfer-encoding': 'chunked', 'connection': 'close', 'access-control-allow-origin': '*', 'content-type': 'application/json', 'date': 'Sun, 12 Apr 2015 16:38:03 GMT'}, b'{"success":false,"api":{"description":"evaluate an ad-hoc Gremlin script for a graph.","parameters":{"rexster.showTypes":"displays the properties of the elements with their native data type (default is false)","load":"a list of \'stored procedures\' to execute prior to the \'script\' (if \'script\' is not specified then the last script in this argument will return the values","returnTotal":"when set to true, the full result set will be iterated and the results returned (default is false)","language":"the gremlin language flavor to use (default is groovy)","params":"a map of parameters to bind to the script engine","script":"the Gremlin script to be evaluated","rexster.returnKeys":"an array of element property keys to return (default is to return all element properties)","rexster.offset.start":"start index for a paged set of data to be returned","rexster.offset.end":"end index for a paged set of data to be returned"}},"message":"","error":"javax.script.ScriptException: groovy.lang.MissingMethodException: No signature of method: groovy.lang.MissingMethodException.idx() is applicable for argument types: () values: []\\nPossible solutions: is(java.lang.Object), find(), any(), find(groovy.lang.Closure), any(groovy.lang.Closure), with(groovy.lang.Closure)"}')

I should add the graph called "graph" is the default graph I find in Rexster and has not been added by me.

So, I have some questions:

How do you connect to Rexster with bulbs (I am certainly doing something wrong)?
How do you create a new graph?