Sorry guys, got a little busy finalising my hackintosh.
In short, the usb problem is a simple one.
There are 8 usb 3s, each one usb 3 counts as two. One usb 3 and one Usb 2. Hence we already have 16.
To fix this, I looked at my DSDT and noted down all the usbs that have the connector 0x3, this means that they're usb3's.
I made a kext in which i inject those usb 3 connectors that i noted down. to get around the usb limit of 15 ports, i used rehabman's FAKEPCIID kexts which redirects the usb 2s from the usb3 ports.
Done!!
It didn't even have an issue with the fact i have reneses. so i will attach the kexts here. but I'm going to make a full guide because some people may have some settings different.
All you have to do is have an untouched DSDT and install the kexts i upload.
THIS IS FOR Z87X-D3H, other boards may need a different injector.
Also make sure you use iMac 12.2 smbios!!!
This problem annoyed me so much, I'm offering help to whoever wants, if you want to Skype and share screen for me to see what your issue is. I'm willing to do it.