Casualty Markers for Napoleon's Battles and further varnish observations

I started with the Napoleon's Battles rules around the same time as Fire and Fury.  What I liked about the latter was the use of figures rather than chits to denote unit status etc. I have been striving ever since to bring the same level of visual appeal to Napoleon's Battles.  

There are plenty of lovely figures to use and these ones from AB are delightful, if a little sad.  My only challenge is that I am not convinced I have yet devised the best way to incorporate markers into units.  What I have are designed to replace a base once a casualty has occurred.  My new thinking is that it would be best if the base was a permanent feature of the unit, incorporating the "command" element as well - which for Napoleon's Battles means the base that has the tag that provides unit information.

This chap had a brief spray of varnish and I am glad that was all it had 

as you can see how it started to mottle on the horse's rump.

This figure had been done some time ago and was varnished back then without trouble.

 On the subject of varnish, this was my test to see if it was the paints I use that was causing the reaction.

From left to right: Jo Sonja, Vallejo, Jo Sonja with a Games Workshop wash and Tamiya.

The problem shows up more on the darker colours in this image.

The clean squares on the bottom colour intersections are from where I applied a top coat of wash.

This seems to readily fix the problem.

The limbers which were badly affected by the varnish have now largely been repaired by painting on varnish (as suggested by Carlo and that partially reduced the problem) and finally by applying a wash.

Needless to say I am no longer using a varnish on my figures (although as per the previous post, I did varnish the Dragon's Teeth without apparent problem - which was at exactly the same time I sprayed the test strip shown above). It remains a mystery.