Error trying to load .abr

Hey folks, I'm trying to load an old (perhaps the operative word here?) Photoshop brush into painter and getting the following message:

[Resource Import] "......brush.abr" cannot be imported as 'brush'.

• I have successfully imported other brushes using the same method.
• I tried clicking the "import resources" button (+) as well as drag-dropping the .abr file, as suggested in the user docs.

I've attached the log file and the brush I'm trying to load, as well as a screenshot of the settings which are active on the PS brush - are there certain things that prevent PS brushes from being transferable? 

Any help would be much appreciated!