Thank you Treetop!
I may try Lowengrin's DCG but will wait for a new computer as my current laptop is rather old and really does not handle IL-2 1946 as nicely as I would like.
I do want to ask, and pardon my persistence, but do you believe there is a way then that I can manually adjust the DCG Campaign executable to mimic what I place in the planesxxx.dat file?
For the GB campaign, I was able to add a field modified Hurricane and it took, but similarly to adding a Tempest, I tried adding a couple of different Spitfires but to no avail.
If adding ANY plane would not take, I would of course give up and try Lowengrin's DCG for sure, but as some planes take and some do not, I am hopeful for a potential fix for the current situation before abandoning all hope.
Thank you once again for your advice.