I have used,liquid latex for years,as a masking agent.I am talking about the thicker stuff,you find in model railroading.I have never had any problems,but then again I am an exclusive enamel user,I tried Model Master acrl. when they first came out,and was not all that impressed,even though I know they have now improved.I haven't built my refit yet,but I am going to use Silly Putty,for masking the windows,its fast,easy,and removes very easily.