I don't know for sure, it depends on changes in the liblzma API. If there were any changes (backward compatible or not, usually nobody cares about forward compatibility), yes, recompiling is required.
bizdelnick
So you need to downgrade to even earlier version. Best of all, use a fork created by Joey Hess.
If you want to control users, don't give them admin privileges.
Most of things you enumerated solve windows specific problems and therefore have no analogs in other OSes.
Kickstart and preseed do not require installing anything. These are features of distro installers. Such configuration management tools as ansible also do nat require installing agent on a target machine (only python is needed, but it is usually installed by default).
Both work. But for desktop use I recommend VirtualBox.
There are automation tools that are much better suited for that then pure shell. Kickstart for anaconda based installers, preseed for debian installer etc. Or configuration management tools.
This does not mean that you won't have troubles because of new software bugs or incompatibilities with old configs.
You can create a shortcut for each firefox profile. This won't give you an isolation like VM or container but similar to portable apps while consume less RAM.
Use vanilla Debian. It is well suited for that purposes and it is great in terms of long time support: stable distro updates almost never break anything and upgrading to new release is possible and relatively simple. Don't listen to those recommending Arch or Fedora, upgrading them is a pain especially when you have to support many servers.
If you want something more lightweight, you may try Alpine. It is also a distro of choice for docker containers. However I'd prefer Debian for the host.
This script won't work in any distro, you have to use a lot of distro specific commands in it. But if you write a script for a specific distro anyway, why not use a tool that distro provides? You'll be sure that it does everything correct way and you even won't need to run anything after installation completed. You can also save time and disk space by excluding packages you don't need but that would be installed by default. You can also automate disk partitioning and customize other installer settings saving even more time.
Speaking about configuration management tools, they can look a bit overkill, but they have at least one advantage of shell script - idempotency. They won't try to install already installed software, change configs that don't need to be changed etc.