At the time of development of the "Rampant Fixed", the current version of Rampant 1.1.1 was practically non-functional. This mod fixed many bugs
However, two years have passed. All this time, "Rampant Fixed" was actively being developed. And now it has a lot of things that the original Rampant didn't have. I agree that the prefix “fixed” no longer fully reflects the essence of the differences. However, it is still suitable because the main problem of the original Rampant - the lack of mutations of existing nests remains and this is "fixed" by my mod
As for you, if you haven't played against a regular Rampant, then "fixed" can be overly difficult, because the biters are significantly smarter and the factions are balanced to require all three types of damage. However, if you play on the normal world to get acquainted with the mod, you can get a lot of fun