1/4" is a fair distance for a template to slip. The various pieces (such as the upper control arm mount) need to be aligned together. Having the upper mount off 1/4" from the lower *is* a big issue.
If the centerline was not scribed properly vertical, the template could have been aligned at one height, but not at another. Again the concern would be that the suspension/steering parts are in the correct orientation relative to one another.
It probably isn't a big problem, but now will be the easiest time to correct anything that you find.
