[Copy By Reference]

I should start by saying I am still a novice to affinity and do not use it on a regular basis (and thus have to frequently revisit certain workflows in the designer). However, I am finding if I want to do certain affects, I might copy a layer and then mask it to another layer. Then I can use layer effects (burn,substract,add,etc) to create this effect over a subselection of the design. This seems to be the best way to get a kind of projected overlay effect where by I can better control a layer blocking another layer but then specially adjust intersecting area using the masked layed. through this process I copy two different layers: one becomes the mask and the other is masked. I also will use the original layers in this effect., so I end up with 3 layers, 1 being the masked layer (a product of copies from the other two).

Now, if at any point in my designing process, I want to revisit changing the original layer used in the mask, such that the outline changes, then this change will not be affected in the masked layer, because I masked via a copy of the layer and this is the only way to do this masked layer operationally, is this correct? There is no solution for this is there?

Likewise if I want to change the original layer which is copied and masked, then the masked layer created from the copy does not reflect the changes in the original layer when I change it and thus I have to repeat the process of creating the masked layer (the same as required to fix the previous mentioned issue). At a fundamental level this is not complex but if I repeat this over multiple layers, it could become tedious. Is there no solution (e.g. Copy by reference -- thus changes are reflected in both places)? Is my workflow wrong? 

[Reducing Letter Spacing]

Thanks everyone. This explanation of kerning versus tracking was very helpful in working with this font as both are needed. Therefore my issue is resolved. 

However, I still don't know if I understand the different between the Character options that change letter spacing (kerning and tracking) versus the Paragraph options. The main difference seems to be that the Paragraph options are somehow trying to determine optimal spacing (and the -100% limit which was causing difficulties with my font)? Is there a good explanation of when I would use one or the other method for working with some typeset section?

[Reducing Letter Spacing]

I have a quick question about Affinity Designer and using the Justification section for Text. I am not a graphic designer but instead am mainly looking to use Affinity Designer to do textures for games. I found a font that's interesting (Ultra Font) but the spacing for the font is actual terrible. I was trying to fix this in Affinity Designer but the letter spacing can only be set to -100%. Is there some other way to solve this letter spacing issue and is there some specific reason for the hardcap here?