Modelling big data query performance - how to improve?

Hello Guys,

this is my model:

The week point is a bridge table here because i have 68 M rows there. 
And now showing some fields from Resources + MEasure to count rows from BridgeTable (Distinctcount rows) is saying that query limit was hit

My meaures (Counting together with Costs caused failures):

New_Resources Count = 
DISTINCTCOUNT ('Dim_EA_Resource_Bridge_Tags'[ResourceIdKey])

New_AmortizedCosts = SUM(Fct_EA_AmortizedCosts[CostInBillingCurrency])

Questions:
1. Is this a usual thing if Power BI has too many records in bridge to cause issues like that? 
2. What should be next step to model this correctly? What can i do? 
3. Counting resources through the bridge table is very heavy if this has 68 M of rows. But this is the purpose to answer how many resources are attached to a specific tag...

my dax is:

// DAX Query
DEFINE
	MEASURE 'MeasureTable'[New_Resources Count] = 
		(/* USER DAX BEGIN */

DISTINCTCOUNT ('Dim_EA_Resource_Bridge_Tags'[ResourceIdKey])
/* USER DAX END */)

	VAR __DS0FilterTable = 
		TREATAS({"Apr"}, 'Dim_Date'[MonthShort])

	VAR __DS0FilterTable2 = 
		TREATAS({"Product"}, 'Dim_EA_Resource_TagKeys'[Key])

	VAR __DS0Core = 
		SUMMARIZECOLUMNS(
			ROLLUPADDISSUBTOTAL(
				ROLLUPGROUP(
					'Dim_EA_Resource_TagKeys'[Key],
					'Dim_EA_Resource_TagKeys'[Value],
					'Dim_EA_AmortizedCosts_Resources'[SubscriptionName],
					'Dim_EA_AmortizedCosts_Resources'[ResourceName],
					'Dim_EA_AmortizedCosts_Resources'[ResourceGroupDisplayName]
				), "IsGrandTotalRowTotal"
			),
			__DS0FilterTable,
			__DS0FilterTable2,
			"New_Resources Count", 'MeasureTable'[New_Resources Count]
		)

	VAR __DS0PrimaryWindowed = 
		TOPN(
			502,
			__DS0Core,
			[IsGrandTotalRowTotal],
			0,
			'Dim_EA_Resource_TagKeys'[Key],
			1,
			'Dim_EA_Resource_TagKeys'[Value],
			1,
			'Dim_EA_AmortizedCosts_Resources'[SubscriptionName],
			1,
			'Dim_EA_AmortizedCosts_Resources'[ResourceName],
			1,
			'Dim_EA_AmortizedCosts_Resources'[ResourceGroupDisplayName],
			1
		)

EVALUATE
	__DS0PrimaryWindowed

ORDER BY
	[IsGrandTotalRowTotal] DESC,
	'Dim_EA_Resource_TagKeys'[Key],
	'Dim_EA_Resource_TagKeys'[Value],
	'Dim_EA_AmortizedCosts_Resources'[SubscriptionName],
	'Dim_EA_AmortizedCosts_Resources'[ResourceName],
	'Dim_EA_AmortizedCosts_Resources'[ResourceGroupDisplayName]

Best,
Jacek