Zeppelin fail to z.show() pandas DataFrame

Question

According to the docs, DataFrames are displayed nicely by Zeppelin if I just do:

import pandas as pd
rates = pd.read_csv("bank.csv", sep=";")
z.show(rates)

But I trying the same wity my DataFrame:

df = pd.DataFrame.from_dict({
    ('a', 'b') : {'value': 1}
}, orient='index')
z.show(df)

it gives:

  Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "<stdin>", line 27, in show
  File "<stdin>", line 43, in show_dataframe
TypeError: string argument expected, got 'numpy.int64'

I thought it was a problem with Multilevel Indexes, but even after using df.reset_index() I can't make it work.

UPDATE

I can also reproduce this with a csv like

id,name,score
a,b,1.1

and using the read_csv method. If I drop the score column, the z.show works.

Is this a known issue? Is there a workaround? Or is it my mistake? I'm using Zeppelin version 0.6.2.