Recognize that when you are working with ADM, everything you are doing is still ABL code, it is just that some of it is part of the framework and you typically just use it, not modify it (although some people certainly do).
If you pick up the 9.1D ADM framework code and put that in your path instead of the OE10 ADM code, then you will have exactly the same code as you do now. Obviously, you need to bring across the ADM source, not just the .rs.
Alternatively, you can try to compile against the OE10 ADM source. Long term, that is clearly a better idea since your framework is evolved and improved and better maintained. But, don't be surprised if there are some changes which will show up as incompatibilities which will require you to modify your own code to suit the OE10 framework.
I have no personal experience with this since I wouldn't touch ADM with a 10 foot pole, but it could be as simple as opening the code in AppBuilder against the OE10 framework and saving the result, but I would be prepared to have to do some fiddling at least.