Just in the final stages of completing my 1/35 Dragon Tiger II with Zim. Everything finished except pigments and had laid down a final coat of Testors Dullcoat Lacquer. I had just purchased AK's pigment fixer and had never tried mud before. While it went on fine using the fixer and the finish stayed flat where the mud was some of the fixer flowed over parts of the upper paintwork and created small areas of semi-gloss finish.

I will attempt to hide them but my question is did this problem occur because of the Lacquer Dullcoat finish? Should I have used an acrylic flat clear instead since the AK fixer is an enamel?? If that is the case can someone please recommend a good acrylic flat finish OR would using an acrylic fixer have fixed this problem. Any help would be gratefully accepted. Thank you.

I just did this with my Panther for the first time. I spray a dullcote after doing the mud.

I would say that you have used too much fixer. Usually you touch the pigment area with the brushtip so it absorbs the fixer, and repeat as needed until all the pigments are wet. Do not brush it everywhere like varnish.