Ok I've got tons of experience with isomalt. You need to add 10 percent water and cook the isomalt to 340 degrees. for best result let it cool to 285 before pouring it out. You should add water soluble colors after the mixture reaches 275. Unlike cookinf sugar you don't need to take much care while cooking becuase the isomalt will not crystallize. Just stir it in the beging of the process untill all the isomalt is melted and then just let it cook. If you need any more help let me know.
Will the isomalt stay clear if cooked to 340 degrees or will it turn yellow?