Firmware and ros combinations

Hi im wonting to no if i can change/downgrade firmwares??
ok so im on 7.16rc4 on my hapax3 and i have 3 caps running 7.14.3 they seem to be running ok
i have been trying and trying to get this ax stuff to work nice and i spent the good part of 7hrs yesterday tweaking and mucking around in importing configs and up dating ros

Now i have it some what stable but the i would like to change the firmware on the hapax3 back to 7.14.3 if i can currently on 7.16.rc4 (seems to be best so far for my situation) but keep the ros on 7.16rc4 or the new 7.17beta2 ???
as there are a lot of fixs and advances there on the later ros and i would like to use some of them if i could
but as we all no the AX series is a mess and i dont really wont to spend hrs again trying to get it stable and get rid of the disconnects and connection losts at -32dbs gggrrrrr very annoying
but i have seen that the 2.4Ghz dont like running on AX speed/freqency as i seen in the 7.17beta2 i can see what roaming and channels it using and it never used ax on the 2.4g
hhhmmmm so i locked the 2.4g at N and seems better and all connected for the capsman and ft and roaming with great speeds no drops

so i have the caps running at 7.14.3 would like to update them but when i do it all goes haywire so there staying at that for the moment
im playing with the hapax3 at moment

im getting roaming but disconnects and lost connections with my mutant config lol
i have done clean config,no config i have try it all nothing seems to work for such issues so now im wondering if i can try older firmware say 7.14.3 is the one everyone raves about that works on the hapax3 with say new ros 7.17.beta2 ???
just like to tinker and see if it makes any difference or not
or do i have to load 7.14.3 on the hapax3 then upgrade the firmware then do a ros update to the latest beta to test hoping it wont break my current mutant config? and then i can have firmware 7.14.3 and ros 7.17.beta2 test mule
thoughts please