I now remember the backwards compatibility issues caused by each version of InDesign having a new default file type and the difficulties it caused when co-creating artwork with people in other organisations. It's all coming back. The requests for the file to be resaved in the compatibility format.
When you open the program for the first time you have to register it with Adobe otherwise it will only work for 30 days.
I had a feeling there'd be something like that. Does this mean that if one were to maintain an offline PC for image editing and DTP, no version of Adobe would be usable without taking that machine online? That would be a shame as there can be good reasons for doing resource intensive jobs on a dedicated machine which stays off the internet and untroubled by automatic updates etc.
All of this seems to make the case for choosing another layout program, as the time spent learning to use it could eventually equal the time spent working around those limitations.
It looks like Scribus is promoted as the open source alternative to InDesign. I've never used it but will investigate it some day. That and DarkTable, the alternative to LightRoom, which looks good. It's just a case of finding time to learn a new tool, and I guess Adobe are banking on enough people not finding that time.
I find that GIMP is best used for complex operations; on the other hand, it is an unwieldy tool for rotating, cropping and scaling images. For these simple edits, other programs do the job quicker. So I have a collection of free image editing programs. Some of those are good for just one thing but they do that thing well. I don't know if that's typical of open source software, but I wouldn't be surprised.