Maryland has a K-1 worksheet like the Federal that allows you to allocate certain items by ration #1-#4 and by amount A-D.

The K-1 properly reflects the SA but the Form 510 is still utilizing the ownership % to calculate the non-resident tax due.  How do I correct that?

The instructions say if you used SA on the federal return the program MAY change the ownership % to reflect the allocation.  That is not happening.