I was shocked, horrified! that some of the lines did not have line numbers.
They do, but SpecBAS now lets you split lines up however you please (with one restriction - you can't split if the new line starts with a number). It checks syntax in the background as you type, so it's more free-form. As far as the compiler (bytecode-ish) is concerned, there are no split lines, and every line has a number.