Usually when one spot like that shows up, it's most likely an area you touched with your finger that had some kind of contaminant on it. You can try sanding but be careful. You may end up with a bigger mess.
I use tamiya glues and have been lucky to never have knocked the bottle over. But my bottle of SOLVASET decal setting solution is a whole different story! Ended up putting that in a old spray paint cap.
Man that look's good. Very clean work. Had to take a second look at the decal on the rear quarter panel. At first I thought it said Little B?tch, Not butch. Love your build