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Mowgli, your confusion lies in that there is no difference in basic strategy for 6 decks & multi decks, regardless of what count you are using, nothing of note anyway, (coupla minor soft doubles changes in 10 or more decks, & some composition dependant ones, none of which amount to anything of significant value.
The difference you note must be attributable to different rules.
Specific to your example, BS is to split 2,2 & 3,3 v 2 & 3 whenever DAS (double after split)is offered, & 2,2 v 3 also in single deck regardless of whether DAS or not. You should also split 3,3, v 8 in single deck if DAS.
If multi deck noDAS, BS is to split 2,2 & 3,3 only vs 4-7.
(strategy obtained from tables in Griffin's Theory of BJ, p174 6th edition.)
Once you own a good sim program like the one you're looking at buying you can generate game specific basic strategy & indices yourself.
I have a powerful sim, but still like the quick reference of Griffin's tables, to quickly work out basic stategy for all common games & rules offered.
BTW KO is a good choice, a very easy count, that gets the money. I play full time with Red 7, which is very similar but a little more accurate if you hop from differing no.s of decks offered without learning new indices. (Assuming of course you start from -2 x the no. of decks in play.) If you only play the one game, or the ability to remember multiple indice lists, KO will work just as well.
Good luck.
