Hi Guido,
I know that this post is old but I hope you'll reply me. I have the same problem with cmos reset on an Optiplex 360 updated to 10.9.5 (from 10.9) but I can't find the EliottForceLegacyRTC.kext you used on the link you provided. Have you solved the issue with that kext?
Thanks
Massimo