Saw this pop up as a newly updated mod, thought I'd give it a go on a (mostly) otherwise vanilla run.
I got the Green 120MJ reactor going pretty easily... although you are required to get Kovarex going before you even try to run a single reactor full-time.
(it takes 268 centrifuges to get enough U-235 for the fuel cells or 134 if you have recycling going)
But once I had a couple centrifuges doing Kovarex and recycling, it is actually U-235 positive.
The statement on the mod page and the Github README, "They require a bit of Plutonium to get started but consume mostly Thorium thereafter" made me think that the Red LFTR would also be mostly self-sustaining with just a bit of Thorium Ore... but it still needs P-239, so you have to run it in conjunction with either 2 LWR or 8 HPWR.
Looking forward to the next stages and seeing where it goes from here.