First of all dude...
Srep mean super reflate , it preprocesses the data for the final tool or finishing one.
Lolz or lzma is a finishing tool (use anyone of them)
And the compression method is like
Precom (like Precom or ztool or xtool)+srep+Lzma(or lolz)
I'm not a special or expert in doing ultraarc thing..
But give it a try using Precom+srep+lolz or lzma
And in arc.ini of unpacking time, if u use cls-srep.dll with .exe (cls one not like srep.exe) u won't have to add any unpacking parameter but surely do use parameters of other tools (lolz either don't require unpack parameter)
#as well as you'll have to add the tools in unpacking section of the setup.exe ( you won't have to change any installer)
Mr.Razor's this post might help you
https://fileforums.com/showthread.php?t=96619