EMC Lineage

I want to have a look at Linux and EMC for CNC

Because I want to try this on an old IBM Thinkpad 760ED I am going to
install Red Hat 7.2 and add the Real time kernel. I see there are are
two lineages of EMC 2.1.16 and 1.1-17.

I am confused by the fact that the Aug 2000 states 2_2_14 which one
would have thought was post 2.1.16.

From the fact that things flip flop from 2.x.x release to 1.x.x I
assume this is the normal Linux thing of one experimental code base
and one more solid code base that work alternates between them. My
question is which is the best code base to go for 2.x.x. or a 1.x.x .
Same question goes for RTL

Before all the "helpful" suggestions I have heard of BDI but I don't
think it applies in my case.

I don't think it would work on the Thinkpad ? lack of display
drivers ( Old level of Red Hat )
It is downlevel Red Hat.
There are other apps I want to install i.e. Eagle, wine
I want to build on AIX skills by picking up some Linux skills.

Thanks