Creating a pareto chart in RapidMiner - rapidminer

Question

I am not able to plot a simple pareto chart.
My data looks like:
and when I try to create a pareto chart, I get a blank space, I also cannot select a value for "Count Value":
What am I missing here?
My sample data is stored in that xml:
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<process version="5.3.015">
<context>
<input/>
<output/>
<macros/>
</context>
<operator activated="true" class="process" compatibility="5.3.015" expanded="true" name="Process">
<process expanded="true">
<operator activated="true" class="generate_data_user_specification" compatibility="5.3.015" expanded="true" height="60" name="Generate Data by User Specification" width="90" x="447" y="75">
<list key="attribute_values">
<parameter key="category" value=""black""/>
<parameter key="Incidents" value="10"/>
</list>
<list key="set_additional_roles"/>
</operator>
<operator activated="true" class="generate_data_user_specification" compatibility="5.3.015" expanded="true" height="60" name="Generate Data by User Specification (2)" width="90" x="447" y="390">
<list key="attribute_values">
<parameter key="category" value=""blue""/>
<parameter key="Incidents" value="2"/>
</list>
<list key="set_additional_roles"/>
</operator>
<operator activated="true" class="generate_data_user_specification" compatibility="5.3.015" expanded="true" height="60" name="Generate Data by User Specification (3)" width="90" x="447" y="210">
<list key="attribute_values">
<parameter key="category" value=""green""/>
<parameter key="Incidents" value="7"/>
</list>
<list key="set_additional_roles"/>
</operator>
<operator activated="true" class="generate_data_user_specification" compatibility="5.3.015" expanded="true" height="60" name="Generate Data by User Specification (4)" width="90" x="447" y="165">
<list key="attribute_values">
<parameter key="category" value=""white""/>
<parameter key="Incidents" value="8"/>
</list>
<list key="set_additional_roles"/>
</operator>
<operator activated="true" class="generate_data_user_specification" compatibility="5.3.015" expanded="true" height="60" name="Generate Data by User Specification (5)" width="90" x="447" y="300">
<list key="attribute_values">
<parameter key="category" value=""red""/>
<parameter key="Incidents" value="2"/>
</list>
<list key="set_additional_roles"/>
</operator>
<operator activated="true" class="generate_data_user_specification" compatibility="5.3.015" expanded="true" height="60" name="Generate Data by User Specification (6)" width="90" x="447" y="480">
<list key="attribute_values">
<parameter key="category" value=""Yellow""/>
<parameter key="Incidents" value="1"/>
</list>
<list key="set_additional_roles"/>
</operator>
<operator activated="true" class="generate_data_user_specification" compatibility="5.3.015" expanded="true" height="60" name="Generate Data by User Specification (7)" width="90" x="447" y="705">
<list key="attribute_values">
<parameter key="category" value=""Gray""/>
<parameter key="Incidents" value="1"/>
</list>
<list key="set_additional_roles"/>
</operator>
<operator activated="true" class="generate_data_user_specification" compatibility="5.3.015" expanded="true" height="60" name="Generate Data by User Specification (8)" width="90" x="447" y="840">
<list key="attribute_values">
<parameter key="category" value=""Navy""/>
<parameter key="Incidents" value="1"/>
</list>
<list key="set_additional_roles"/>
</operator>
<operator activated="true" class="generate_data_user_specification" compatibility="5.3.015" expanded="true" height="60" name="Generate Data by User Specification (9)" width="90" x="447" y="570">
<list key="attribute_values">
<parameter key="category" value=""Purple""/>
<parameter key="Incidents" value="1"/>
</list>
<list key="set_additional_roles"/>
</operator>
<operator activated="true" class="append" compatibility="5.3.015" expanded="true" height="220" name="Append" width="90" x="715" y="120"/>
<connect from_op="Generate Data by User Specification" from_port="output" to_op="Append" to_port="example set 1"/>
<connect from_op="Generate Data by User Specification (2)" from_port="output" to_op="Append" to_port="example set 5"/>
<connect from_op="Generate Data by User Specification (3)" from_port="output" to_op="Append" to_port="example set 4"/>
<connect from_op="Generate Data by User Specification (4)" from_port="output" to_op="Append" to_port="example set 2"/>
<connect from_op="Generate Data by User Specification (5)" from_port="output" to_op="Append" to_port="example set 3"/>
<connect from_op="Generate Data by User Specification (6)" from_port="output" to_op="Append" to_port="example set 6"/>
<connect from_op="Generate Data by User Specification (7)" from_port="output" to_op="Append" to_port="example set 9"/>
<connect from_op="Generate Data by User Specification (8)" from_port="output" to_op="Append" to_port="example set 7"/>
<connect from_op="Generate Data by User Specification (9)" from_port="output" to_op="Append" to_port="example set 8"/>
<connect from_op="Append" from_port="merged set" to_port="result 1"/>
<portSpacing port="source_input 1" spacing="0"/>
<portSpacing port="sink_result 1" spacing="0"/>
<portSpacing port="sink_result 2" spacing="0"/>
</process>
</operator>
</process>

Answer 1

So I found a workaround (thanks to Andrew), which is only working for this example set.
I had to "de-aggregate" it and add a new polynominal attribute with the same value for every example.
Then I could create a Pareto chart, group-by 'category' and set the count-column to the new attribute.
Lead to this chart:
When I do this with my dataset I get this chart:
I guess without being able to configure the pareto chart, it is really bad for a lot of different values in the group-by category.