It's case sensitive.. It was reported on aCis forum long time ago, and honestly I don't remember what was the trick to fix it.. Changing " to ' or changing big letter to small one, not rly sure. Well, use current aCis files and you should be okay.. I guess :)
Well, it was about classes folder, so replace with attached one and give feedback :)
Btw.. I'd suggest you to don't use esios, it's really outdated, since it's based on aCis 270 rev, something like that..
I found it, it has been fixed at rev 278.. You see.. Esios is rly behind.. Screw that customs and use actual aCis, try to adapt some customs from esios or so :]
classes.zip