Seems that Strata have some problem on retro-gen...
When I added it the console started spamming errors, and I've tracked down a "blaming on factorization", then I removed factorization, but the server still spam alot of errors and then after 4-5 minutes it end up in a crash
These are the crashes before and after factorization http://pastebin.com/SbSBkDKL
http://pastebin.com/ypa0JtBv

and this is the fml-latest-log http://www.mediafire.com/download/zmfuf544nx19cwz/fml-server-latest.log

seems this doesn't occur if I generate a new world.....

I noticed Thermos is installed. Could you try again without Thermos?

Ok, I've actually tryed that, same error, the only difference is that with bad-performance forge vanilla server it takes more time to load;
this is the crash report http://pastebin.com/K9L6TaUz

and this is the full log http://www.mediafire.com/download/tx9o0ozs2dmx3c9/fml-server-latest.log

I hope this could help..

Hey man.. have you find a solution? :/