Fish eye and beading are almost always a surface contamination problem. In this case, the source of the "contamination" may well have been the Tamiya gloss Brilliant Blue from the rattle can. High gloss enamels often contain a small amount of silicone additive that migrates to the surface during the final stages of cure. It makes the surface very shiny, and nearly impervious to any water based solvent—or even other enamel paints. I strongly suspect this is the problem, since both Tamiya and Gunze have had similar problems reported in the past.
The cure is simple: either sand the surface with very fine grit (2000+, or the paint polishing kits you car guys use to produce a "candy apple" finish); or wipe the surface thoroughly with 90% isopropyl alcohol, denatured alcohol, or ethyl alcohol. If you use the alcohol wipe method, test the alcohol on a spare decal from the same sheet to insure that it will not adversely affect the ones you've put on the model.