"Overlaid" or "overlain" as an adjective [closed]

There are two different verbs at play here:

1. Overlie; past overlay, past participle overlain.

   1. to lie over or upon, as a covering or stratum.
   2. to smother (an infant) by lying upon it, as in sleep.

2. Overlay; past overlaid, past participle overlaid.

   1. to lay or place (one thing) over or upon another.
   2. to cover, overspread, or surmount with something.
   3. to finish with a layer or applied decoration of something: wood richly overlaid with gold.
   4. Printing. to put an overlay upon.

The meanings overlap somewhat, but while "A overlies B", "I overlay A on B". Hence it is overlay that is used of superimposed images. It is also overlay that exists as a noun for such a superimposed or covering item.

Hence, you want overlaid.

Better still, just use the plural noun overlays (all the more so, since the components are not overlaid while stored in separate files, but overlay the noun does include things that are intended to be overlaid, as well as things that currently are overlaid, and the term has an established use in terms of superimposed computer images).