Not the answer to your question, but merely moving from Mac to PC should not be causing text to go overset. Seems likely you've got a font substitution, or perhaps you've also changed the version of ID, or both.
Do you have an object style assigned to the text frames? Perhaps redefining the style to include auto-sizing will solve the problem.
Yeah it will be the substitution and most likely the ID, the files were not previously made by myself so not 100% sure of the version used.
There seems to be no object style added to the text frames which have the over set text, slightly wary of changing the frames to auto size as it isn't normal text, will give it a test however, thanks.
Work on a copy....
You could redefine the [Basic Text Frame] style (which is probably what it is if there's not another defined), let the frames grow, the redefine it again to remove the auto-size and I think the frames would remain the correct size, but I haven't tested.