I would like to help. I have just successfully completed the exact process you are trying to work through, and I would like to provide a "recipe", including step-by-step pictures as well as written instructions. But I'm still not clear on exactly what your status is:
(1) Your A16 firmware MUST be at 1.81. Have you successfully updated your A16 to that level? If not, what is the problem you are facing that prevents the firmware update process from completing? We need to get your A16 firmware updated to 1.81 first. Are you there, or not?
(2) Assuming your A16 is at 1.81 firmware, the migration of A8 PRIR and HPEQ files to the A16 is a straightforward procedure with several steps. The initial steps relate to preparing the microSD card for use in the A16.
As has been previously stated, the A8 files to be imported to the A16 must be in the "version 2 format", meaning they have file names PRIR2xxx and HPEQ2xxx. This is the standard naming convention used by the latest firmware (August 3, 2011) for all A8 units when writing out PRIR and HPEQ files to the SD flash card. Internally A8 units can use either original PRIR0xxx/HPEQ0xxx files or PRIR2xxx/HPEQ2xxx files. But the A16 can only import the new PRIR2xxx/HPEQ2xxx format.files.
So if you have the older format files being used internally on your A8, you must first WRITE THEM OUT TO SD FLASH CARD in order to get the old format files converted to new format, so that they can then be imported into the A16. Once written out to SD flash media on the A8, you would then read them back from the SD flash media into your computer so that you could then write them out from the computer to a microSD flash card for use in the A16.
(3) Assuming you now have new format PRIR2xxx/HPEQ2xxx files available on your computer
(a) format the microSD flash drive as FAT32,
(b) create a "parent folder" at the root of the microSD flash drive named \Realiser,
(c) create two sub-folders under \Realiser named \PRIRS and \HPEQS,
(d) copy your A8 PRIR files (with standard 8.3 file names PRIR2xxx) to be imported into the A16 from computer into \Realiser\PRIRS
(e) copy your A8 HPEQ files (with standard 8.3 file names HPEQ2xxx) to be imported into the A16 from computer into \Realiser\HPEQs
(f) "safely remove hardware", EJECT the microSD flash drive, and you're ready to use it on the A16.
By way of example, the new PRIR I just created using my A8 is named PRIR2011.SVS. I want to import it into the A16. Here is what my microSD flash card looks like after following the above steps (formatted as FAT32 with "label" of SMYTH), with PRIR2011.SVS placed in the \Realiser\PRIRS sub-folder: