Can't change Block message in Trip Search Block Config

Just installed Trip Search, on a 4.6.2 installation, and can't seem to set the Block Message for the Trip Search block.

I'm not sure where it's going wrong. When I tried putting in some error check breaks in the "save" area of the block function trip_search_block() , the variable $edit seemed to be NULL, before it got to the line:

variable_set('trip_search_block_message', $edit['trip_search_block_message']);

But it's the same variable (isn't it?) that is used to set the other non-block-specific features, (like Custom visibility settings) which _does_ work.

The function _looks_ to be structured the same as other blocks with custom settings, which do work... so I'm not sure where the $edit variable is getting lost. I was hoping it was a fix that a Drupal amateur could handle, but apparently it's not. Or at least not _this_ amateur. : )

Anyway, I'd really like to be able to change the message without hard-coding one in or manually altering the database. : )