Multi-selects in Gravity Forms only passing first value for each custom taxonomy


I've posted a support request here as the problem may be related to the Gravity Forms + Custom Post Types plugin. However, according to another user with a similar problem, the issue was caused by Advanced Custom Fields (ACF) so I figured I should ask here given that CustomPress is similar.

I have three custom taxonomies setup. I also have a submission form setup that allows users to submit resources and select multiple "tags" for each taxonomy out of the automatically generated list (using the multi-select field in Gravity Forms). The submission works correctly (the multiple values show up) but the post only contains the first value chosen for each taxonomy.

Appreciate any input here...