Brush Editing Freeze

[ChristiduToit]

I've been experiencing a number of app freezes on my iMac while creating a custom brush for a project this morning.
Creating a new brush is easy, but as soon as I start changing the values of the "Size" and/or "Spacing" (although I haven't even tried changing other options) in the brush editor, I get the spinning rainbow wheel. 
I hoped that the app was just processing the request to change those values (and taking a bit longer than usual), but it ultimately froze up completely, resulting in me having to Force Quit Photo. 
Upon reopening, I tried it again, and the same thing happened over and over again.

All I created was a standard Round brush, and when trying to change the values in the brush editor, I experienced app freezes every time, without fail.
Entering the value is not an issue, but pressing 'tab' to enter the next value section, or simply clicking in the next box with my mouse results in a total freeze.

[ChristiduToit]

Just to add to my previous post. It seems that this freeze occurs when doing just about anything that involves editing the brushes, including deleting brushes. 
I deleted a brush from the category list and the app froze. Upon reopening I realised that it had deleted my entire category along with all my custom brushes. 
Luckily I had a back-up file for the brushes, but that could have ended a lot worse if I hadn't.

[carl123]

(Assuming you have full backups of your custom brushes)

In Preferences, Miscellaneous, Reset your brushes  (location may be different on a MAC?)

Then test to see if you can create, modify & delete a brush without freezing

If you can, restore your Custom brushes and try again