Well now time as passed, lot of theaters ONLY on 128 segment size have been build, more theaters are helped to born and so on. Lot of experience on the theater building on my sleeve I decided to try out 256 segment theater building once again...
I did everything by the book and what happens? it works.
We have to understand that the size of the 256 segment theater is just mind blowing. As the default size is 64 and 128 theaters are "huge" compared to that, the 128's are little boyscouts compared to the big bad 256 segment theater.
The TGA image to create the TE/Campaign map is on 8096 x 8096 resolution and the size is about 65mb for that file. Yeah, think about theater download sizes, just a background image.
Tacedit job for 256 theaters is pretty easy, just change the theater size and thats it, no big deal.
The game TE/Camp map itself lags a bit on my 1.3ghz, 512mb ram computer but only to that point that you notice like "hey, were not in 128 theater anymore", its still fully playble. This is because the huge 65mb size.
In game I got it to run nicely on IA, TE and Campaign. The TE however has still the same issue as 128 had earlier when you save a mission and try to reload it, you get CTD. The campaign I had was just a small test one with 4 objectives and some squarons. Flights got scheduled etc, no problems there.
I got average reading on the bottom left corner to top right corner distance on the 256 theater and it was about 3000 miles, now if that doesn't take few air refuells I dont know what does

Anyways just wanted to post that if anyone ever thought of the situation with 256 theaters... It can be done.
PMC TFW
Snake Man