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If XOOPS 2.2.3 works for you, then use it.
However, there have been some central bugs that once found and fixed, made other bugs elsewhere.
There are NO security holes reported in 2.2.3, purely functional problems.
Basically, if login works, text shows up correctly and the modules you need work on 2.2.3, I see no problem in using it.
More modules work with 2.0.13.1 and it is more mature, meaning that some bugs are there, but they are usually just nuisances and not fatal.
"When you can flatten entire cities at a whim, a tendency towards quiet reflection and seeing-things-from-the-other-fellow's-point-of-view is seldom necessary."
Cusix Software