Good question!
As far as I’m aware - everything that we’ve been hooking into from the Unreal API has been pretty stable so both earlier versions to a point and later versions should be fine.
Right now the Skookum UE4 Plug-in is at Unreal 4.5.1 also. We will be getting the latest 4.6 in the next few days and determine if anything has changed. For the last few UE4 versions there were no code changes that needed to be made with the Skookum plug-in. [It might take a bunch of lengthy recompiles - but we might be able to find out the earliest version of UE4 that works without requiring code changes to the Skookum plug-in.]
There are a few changes to the Unreal Engine core runtime that we will be pushing to the main branch soon that allow some deeper debug functionality. For things like that and other changes for future versions we can probably give light code patches to get things up and running to keep older Unreal versions backwards compatible to the plug-in. You would have to build the Unreal Engine from code rather than just using a pre-built version, but that should be fairly easy.
The source for the plug-in itself will also be available so you can always try to tinker with it yourself too. All the calls to the native API will be available for you to extend in any crazy way you like and they are 100% independent from Unreal so are completely resistant to Unreal version changes. We’d like to create some sort of mechanism for people to submit useful changes that they’ve added to the plug-in too. Allowing people to submit their own backwards compatibility Unreal patches is a good idea.
There are essentially three plug-in modules for the UE4 plug-in and each may be more or less UE4 version dependant:
- **Skookum runtime **- this is pretty independent and should be pretty stable and resistant to UE4 changes
- **Skookum Header Tool Generator **- this gets the command bindings used with Blueprints and adds them into Skookum. Probably fairly stable - or the meta info for thousands of bindings to commands would also need to be changed.
- Skookum UE4 Editor - these are hooks into the Unreal editor for convenience calls to the IDE and other ways that Skookum scripts can interact with the Unreal editor. This is probably the most volatile area. Though it isn’t 100% necessary and older versions of the plug-in could be used if major changes occur with the UE4 editor.