Dax help: Shadow context with allselected()

Hello All,

I really need your help.  All of my numbers are wrong in production.

I need to create a ratio whose denominator is dynamic and is determined according to the report filter.

I created this measure using the allselected function.

But I have incomprehensible results when I create other measures from this first measure.

I read an article by Marco Russo which talked about shadow context.

I would like to know if you have any trick to override the ALLSELECTED () function?

Thanks