Sort Order ignores measure??

DJSwezey , This will work well when you have separate week table with rank on year week column.

Have a separate date/week table joined back with your table

Have these new columns in Date Table, Week Rank is Important in Date/Week Table

Week Rank = RANKX('Date','Date'[Week Start date],,ASC,Dense)
OR
Week Rank = RANKX('Date','Date'[Year Week],,ASC,Dense) //YYYYWW format

cumm = CALCULATE(sum('Table'[Qty]), FILTER(ALL('Date'),'Date'[Week Rank]<=max('Date'[Week Rank])))

I think simple formula with date will also work

Cumm Sales = CALCULATE(SUM(Sales[Sales Amount]),filter(all('Date'),'Date'[date] <=max('Date'[date])))

or

Cumm Sales = CALCULATE(SUM(Sales[Sales Amount]),filter(allselected(date),date[date] <=max(date[Date])))

consider new window function with date or week

Cumm Based on Date = CALCULATE([Net], Window(1,ABS,0,REL, ALL('date'[date]),ORDERBY('Date'[date],ASC)))

Cumm Based on Date = CALCULATE([Net], Window(1,ABS,0,REL, ALLSELECTED('date'[date]),ORDERBY('Date'[date],ASC)))

Power BI — Week on Week and WTD
https://medium.com/@amitchandak.1978/power-bi-wtd-questions-time-intelligence-4-5-98c30fab69d3
https://community.powerbi.com/t5/Community-Blog/Week-Is-Not-So-Weak-WTD-Last-WTD-and-This-Week-vs-Last-Week/ba-p/1051123
https://www.youtube.com/watch?v=pnAesWxYgJ8
Time Intelligence, Part of learning Power BI https://youtu.be/cN8AO3_vmlY?t=27510

Power BI Window function Rolling, Cumulative/Running Total, WTD, MTD, QTD, YTD, FYTD: https://youtu.be/nxc_IWl-tTc