[Plugin: Custom Field Template] Keys with spaces not outputting…whats wrong with my shortcode?

WordPress 3.0
Custom Field Template 1.7.1 ( latest )

My custom field metadata is not showing up on my posts if I have a space in the custom field keyname. Any ideas what I’m doing wrong?

The following does not work for me:
I’m using the short code in my post: [cft key=Rate_Adult]

And I’m using this as the custom field key: [Rate Adult]

However this does work: ( noticed I removed space in the field key )
[cft key=RateAdult]
[RateAdult]

Is my short code incorrect? Sorry to ask but the documentation seems pretty slim on this. Thanks for any ideas.