Does anyone have any information on how accessible this tool is to disabled users?

Does anyone have any information on how accessible this tool is to disabled users?

I am particularly interested in screen reader access and the ability to access the page using only the keyboard (i.e. without the mouse). I've found a few posts that mention problems with accessibility, but none seem to suggest these have been solved.

I am visually impaired myself and wish to use this tool to work with other visually impaired people. I am aware of the CAPTCHA for sign up which does not have an accessible equivalent, but I have a way around that for my users.

Hope someone can help,

Emma