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How to calculate the slide parameter for OsxAptioFix2Drv

If you cannot boot because of an error like "couldn't allocate runtime area, error allocating 0xXXXX pages (...)" with OSXAptioFIX2 then your memory is too fragmented. You need to manually "slide" the pointer of the OSXAptioFix2 to a free continuous map of at least the size of 0xXXXX in your memory.
Because this memory map is unique to each system configuration you have to use a different slide command on most computers.

Step 1: Get Memory Map

Boot into the UEFI Shell from Clover and enter the command memmap. You'll get an output similar to this MEMMAP

Step 2: Use hexadecimal calculator

use a hexadecimal calculator.
You can use the Mac OSX Calculator in Programmers Mode. You can switch this by the option View->Programmer. Switch the calculator to hex mode by pressing the button labelled 16 (see the buttons 8|10|16) Calc

Step 3: Add the number of pages till first suitable block

Look at the column #Pages (N Pages) for a bigger hexadecimal number than the one in your error message. The column Type has to be set to Available. Then apply the following formula for your calculation:

OLD CALCULATION (older CLOVER)

(START - 100000) / 200000
Each integer in slide will move the pointer 200000. It begins at 100000.

NEW CALCULATION

(START / 200000) + 1

Look in your memmap for the first Available block with enough pages. The slide parameter doesn't work with high numbers, so you should look for the one with the smallest Start value.

Example with memmap from Step 1 and the old calculation:

Error: Error allocation 19322 pages  
Optimal START = 0x6B78000 with 0x1DA8F pages available  

(6B78000 - 100000) / 200000 = 35. This is NOT your slide parameter!

Step 4: Switch to Base 10

convert the number to Base10. You can do this with the mac os calc by pressing the button with the 10 on it.
Example: 0x35 => 53

This is your slide parameter. Enter it in your boot command (for example slide=123) and the system should boot up like normal. If it doesn't then maybe your block doesn't have enough free pages and you have to select a bigger one. It's also possible your memory is too fragmented to slide at all or the kernel requests more pages, which are not slideable. In such a case you can use the (unstable) ./10.12/CLOVER/drivers64UEFI/Other/OsxAptioFix2Drv-free2000.efi. More info: see Step 7 of the tutorial