I'm currently still struggling with Einstein Analytics and Discovery Insights Specialist (https://trailhead.salesforce.com/en/content/learn/superbadges/superbadge_analytics_insights_specialist?trailmix_creator_id=briankessler&trailmix_id=getting-started-with-analytics) Challenge 2:

My SAQL query is now:
 

beattieSubscribers = load "Beattie_Subs";
tenuredSubscribers = filter beattieSubscribers by row(
               Tenure_Length.selection, 
               [0], 
               ["min","max"]
          ).asRange("Tenure");
churnSubscribers = filter tenuredSubscribers by 'Churn' == "Yes";
groupedSubscribers = group tenuredSubscribers by all full, churnSubscribers by all;
churnRate = foreach groupedSubscribers generate (count(churnSubscribers) / count(tenuredSubscribers))*100 as 'churnRate';

However, this results in the following error displayed on the page:
 

Function doesn't have a type check definition:

.
What is wrong here and how can/should I fix this?

Thanks?

I'm stuck on step #2 of Einstein Analytics and Discovery Insights Specialist superbadge.  I'm getting this warning while checking the challenge:

The step "Churn Tenure' is in compact form, so the filter values need to be specifed as a minimum and maximum
The static step that feeds has the following the value:
 

"Tenure_Length": {
                "broadcastFacet": false,
                "label": "Tenure Length",
                "selectMode": "single",
                "type": "staticflex",
                "values": [
                    {
                        "display": "High Risk",
                        "value": "1 to 12 months",
                        "min": 1,
                        "max": 12
                    },
                    ...
                ]
            }

I'm using selection binding for min and max values.  The dashboard is correctly filtering:


Any ideas? 
I've tried a non-compact form step where I inject a saql fragment into the query, as well as where I inject min/max values using a range filter serialization...All these efforts end in the same challenge failure message.

Any help/suggesitions are welcome!