Your email address, if given, is not shown on-screen.
The final ID sequence is that you should enter a series of five digits in reverse order. It's a lot better, I feel, than those hard-to-read check images that some sites provide. For your assistance, note that the sequence is always numerical - zero is zero, one is one. No letters to muddle up...
To aid in your writing, you can include HTML glyphs. For example, to write "日本語" (ni-hon-go, or Japanese in Japanese!), simply write "日本語".
Note that if you wish to write a single ampersand '&' character, you should write "&". If you forget, most decent browsers will automatically correct this, but some may not, or may not do it entirely as you wanted...
You cannot embed HTML.
You may also wish to include linebreaks. Simply press Enter and leave such linebreaks in your comment text...
0.01 - Initial, basic, buggy version.
0.02 - Now asks for, and checks, email address. Bodge to prevent endless lines messing up wrapping.
0.03 - Now asks for a verification code. Entry form slightly redesigned. Various modifications to permit Japanese ideographic characters to be used. Added \n and \p support. Upon an error, a try-again appears so you don't have to entry the comment all over again as people probably wouldn't bother...
0.04 - Made the email address optional.
0.05 - Now reports a brief message if there are no comments to display.
0.06 - Now creates an RSS file for comments posted.
0.06b - Minor modifications for changes in layout in the b.log2 system.
0.07 - Removed \n and \p support. Now? Just press Enter and make the appropriate newlines in the comment text!
0.07b - Minor tweaks for b.log2 revisions.
0.08 - Output was missing </tr> tags (browsers assumed this behaviour anyway, so no difference in rendering). Fixed. Also removed note about not needing obscure codes for newlines. Pushed the "Submit" button to the right, more in line with typical GUI styling.
0.08m - Revisions to the mobile part to support simple comment entry on mobile devices. Desktop side not altered.
0.09/0.09m - David Pilling drew my attention to vanishing comments due to an oddity in how the server behaves when it runs out of allocated space. Because of this, the comment code will attempt a dummy write to a test file, and if that fails, comment addition will be disabled. Fixed bug where early exit (due to no date being available) would terminate php execution too early. Fixed issue where mobile help image had watermark stuck across the bottom (and it obscured content due to restricted palette). Fixed some other minor stuff too trivial to mention. ☺