>
> I would expect the following two expressions to produce pulse effects 
> that differ in colour (tried with emacs -Q):
>
>    (pulse-momentary-highlight-region (point-at-bol) (point-at-eol) 'highlight)
>    (pulse-momentary-highlight-region (point-at-bol) (point-at-eol) 'region)
>
> Instead they use the background of pulse-highlight-start-face.
>

Indeed; patch attached.