More details:

Line 197 of Store.js

LABKEY.ext.Store.superclass.constructor.call(this, {
            reader: new LABKEY.ext.ExtendedJsonReader(),
            proxy: this.proxy ||
                    new Ext.data.HttpProxy(new Ext.data.Connection({
                        method: 'POST',
                        url: (config.sql ? LABKEY.ActionURL.buildURL("query", "executeSql", config.containerPath, qsParams)
                                : LABKEY.ActionURL.buildURL("query", "selectRows", config.containerPath)),
                        listeners: {
                            beforerequest: {fn: this.onBeforeRequest, scope: this}
                        },
                        timeout: Ext.Ajax.timeout
                    })),
            baseParams: baseParams,
            autoLoad: false
        });


Where "url" evaluates to:

(config.sql ? LABKEY.ActionURL.buildURL("query", "executeSql", config.containerPath, qsParams)
                                : LABKEY.ActionURL.buildURL("query", "selectRows", config.containerPath))

"/query/Studies/SDY80/selectRows.view"


and

JSON.stringify(baseParams)
"{"schemaName":"study","query.queryName":"IRP_all","query.param.pids":"SUB114450.80","apiVersion":9.1}"


So that fails per the error above...